State tax docs / States / New Mexico

New Mexico state income tax: engine rules, 2026

How the QuantCalc engine computes New Mexico tax for tax year 2026, rule by rule, with the official source for each rule. Verification status: Worksheet-tested (what this means).

On this page: How the tax is computed · Rate schedule · Deductions, exemptions and credits · Age 65+ subtractions and credits · Social Security · IRA, 401(k) and private pensions · Public pensions · Military retirement pay · Roth conversions · Capital gains · Blindness and disability · Part-year and nonresident returns · Worked examples · After 2026 · Not calculated · Verification. Machine-readable: this state's entry in the engine config and the provenance file (key NM).

How the tax is computed

Every step the engine takes for New Mexico, in the order it takes them. Steps marked with a filing status or household type apply only there. Each step links the section below that carries New Mexico's figures and the official sources for it; the calculation order page describes every step for all jurisdictions.

What each filing status gets, read back from the engine for a household with $1 of income (so below every phase-out and income test):

	Single	Married filing jointly	Married filing separately	Head of household
Rate schedule used	single schedule	joint schedule	joint schedule, thresholds halved	head-of-household schedule
Top rate	5.9% from $210,000	5.9% from $315,000	5.9% from $157,500	5.9% from $315,000
Standard deduction, under 65	$16,100	$32,200	$16,100	$24,150
Standard deduction at 70 (joint: both 70)	$18,150	$35,500	$17,750	$26,200
Personal exemption	$2,500	$5,000	$2,500	$2,500
Age subtractions at 70 (joint: both 70)	$8,000	$16,000	$8,000	$8,000

Per-person mode joint returns with the spouse's age given On a joint return with the spouse's age given, every age test the state applies per taxpayer is evaluated for each spouse at their own age. Without it one household age applies to both.
engine step (compute_state_tax_detail). Engine convention, no external source: The engine cannot know the second spouse's age unless told.
Blindness and disability, per person only when the caller says a person is blind or disabled The filer is person one; the spouse counts only on a joint return and only when the caller says so (there is no household convention as for age). Where a state lets a disabled person (and, where it says so, a blind one, or one whose spouse is disabled) qualify for its general retirement exclusion before the age, that person is treated as having reached the age for that exclusion only. Of the 42 taxing jurisdictions, these have a blind amount: Arizona, Arkansas, California, Colorado, Delaware, the District of Columbia, Hawaii, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, Nebraska, New Jersey, New Mexico, North Dakota, Oklahoma, Oregon, Utah, Vermont and Virginia; these have none: Alabama, Connecticut, Georgia, Louisiana, New York, North Carolina, Ohio, Pennsylvania, Rhode Island, South Carolina, West Virginia and Wisconsin. A disability route is calculated in Arkansas, the District of Columbia, Georgia, Hawaii, Idaho, Iowa, Maryland, Michigan, New Jersey, Oregon and West Virginia.
engine step (compute_state_tax_detail). Engine convention, no external source: Who is blind or disabled is the caller's statement; the engine has no household convention for it.
Rate schedule and standard deduction by filing status Single uses the single schedule and deduction; married filing jointly the joint ones. Head of household and married filing separately follow the two steps below.
New Mexico's values · engine step (select_brackets). Sources (Rate schedule): FYI-104 New Mexico Withholding Tax (Rev. 11/2025), wage withholding tables effective January 1, 2026 (checked 2026-10-12); HB0252 (checked 2026-09-27); 2025pit 1 ins (checked 2026-10-12)
Married filing separately Where the state publishes its own separate schedule, that one (with half the joint deduction unless a separate deduction is set). Where one schedule applies to every status, that schedule unscaled with the single deduction. Otherwise the joint schedule with every threshold and the deduction halved (computed as the joint tax on twice the income, halved).
New Mexico's values · engine step (select_brackets). Sources (Rate schedule): FYI-104 New Mexico Withholding Tax (Rev. 11/2025), wage withholding tables effective January 1, 2026 (checked 2026-10-12); HB0252 (checked 2026-09-27); 2025pit 1 ins (checked 2026-10-12)
Head of household The state's head-of-household schedule where it has one, else the single schedule; the head-of-household deduction where set, else the single deduction.
New Mexico's values · engine step (select_brackets). Sources (Rate schedule): FYI-104 New Mexico Withholding Tax (Rev. 11/2025), wage withholding tables effective January 1, 2026 (checked 2026-10-12); HB0252 (checked 2026-09-27); 2025pit 1 ins (checked 2026-10-12)
The income total every income test uses Other ordinary income + retirement distributions (before any exclusion) + conversion + federally taxable Social Security + long-term gains + Railroad Retirement Tier 2. It stands in for federal adjusted gross income in every threshold, cliff and phase-out below; state subtractions do not reduce it.
engine step (compute_state_tax_detail). Engine convention, no external source: The inputs are the federal AGI components, so their sum is federal AGI for these income types.
Attributing income to each spouse joint returns with each spouse's own amounts given With a caller's split (the API's spouse object), each spouse's own distributions (employer-plan money included), pension, public pension, conversion, wages and military pay; spouse 2's shares are clamped into the household totals and spouse 1 gets the rest. Without a split, in per-person mode, every item is divided 50/50. Social Security is divided by each spouse's own gross benefits where the caller gives spouse.socialSecurityGross, else 50/50; other ordinary income and gains are always divided 50/50 where a rule needs a per-person amount. The split is used only where a state's rule is per taxpayer; household totals stay authoritative for the base and the income tests.
engine step (compute_state_tax_detail). Engine convention, no external source: Equal attribution is the neutral split when the owner of a dollar is not known.
Keeping the per-spouse shares inside the household joint returns with each spouse's own amounts given After the public-pension and employer-pension carve-outs, if the two spouses' remaining shares add up to more than the household's exclusion-eligible distributions (an inconsistent split), spouse 1's share is reduced so they do not.
engine step (compute_state_tax_detail). Engine convention, no external source: Input normalisation.
Military retirement pay The state's military rule runs first, on military pay alone, per taxpayer: each spouse's own pay at their own age when attributed, otherwise half each at the household age on a joint return. Exempt dollars leave the base; the rest become pension dollars for the general retirement rules. Where the state lets a disabled retiree qualify at any age, a disabled person is treated as having reached the rule's age.
New Mexico's values · engine step (compute_state_tax_detail). Sources (Military retirement pay): 2025pit adj ins (checked 2026-10-12)
One taxpayer's military exemption Exempt: all of it (below the age split, up to the younger cap). Capped: up to the cap for the age tier, plus the earned-income bonus below the age split when the taxpayer's own wages exceed the threshold, less the taxpayer's own Social Security where the rule says so. Percentage: the percentage (below the age split, up to the younger cap). Then the income limit: above it the exemption is lost, or phased out over the range where one is set.
New Mexico's values · engine step (military_exempt_one). Sources (Military retirement pay): 2025pit adj ins (checked 2026-10-12)
Capital-loss deduction off the base The deduction comes off the other ordinary income (negative income, as Form 1040 line 7a is), so the base and every state-AGI figure summed from it carry it; WI no more than Wisconsin ordinary income (Schedule WD line 28(c)). States whose base is federal taxable income (with the caller's figure) already have it there and take it only once. Engine 1.13.1: the allowed rental loss comes off the same way, on its own line (rental_loss_deduction).
New Mexico's values · engine step (compute_state_tax_detail). Sources (Capital gains): Instructions for 2025 PIT-ADJ, Schedule of Additions, Deductions, and Exemptions (checked 2026-10-12); 2025 PIT-ADJ Instructions (checked 2026-10-12); 2025 PIT-1 Instructions (checked 2026-10-12); 2025 Schedule D (Form 1040), Capital Gains and Losses (checked 2026-10-12)
Which Social Security threshold applies Joint returns use the joint threshold; head of household uses it too where the state says so, otherwise the single one; married filing separately uses its own threshold where set, else the single one. Benefits are tested against the income total above.
New Mexico's values · engine step (ss_amount_in_state_base). Sources (Social Security): Instructions for 2025 PIT-ADJ, Schedule of Additions, Deductions, and Exemptions (checked 2026-10-12); Social Security Income Tax Exemption (checked 2026-10-12)
Social Security: exempt up to a threshold, then all At or below the threshold nothing enters; above it the whole federally taxable amount does (a cliff).
New Mexico's values · engine step (ss_amount_in_state_base). Sources (Social Security): Instructions for 2025 PIT-ADJ, Schedule of Additions, Deductions, and Exemptions (checked 2026-10-12); Social Security Income Tax Exemption (checked 2026-10-12)
Retirement exclusion (household) The distributions eligible for the exclusion go through the exclusion below. Taxable public-pension dollars left by a cap are not eligible; below the IRA age only employer-plan dollars are.
New Mexico's values · engine step (compute_state_tax_detail). Sources (IRA, 401(k) and private pensions): Instructions for 2025 PIT-1 New Mexico Personal Income Tax Return (checked 2026-10-12); Instructions for 2025 PIT-ADJ, Schedule of Additions, Deductions, and Exemptions (checked 2026-10-12)
Conversion taxed or exempt In full-exclusion states a conversion is exempt at the qualifying age (at any age where the state says so). Elsewhere, unless pooled above, it is ordinary income taxed in full.
New Mexico's values · engine step (compute_state_tax_detail). Sources (Roth conversions): Instructions for 2025 PIT-1 New Mexico Personal Income Tax Return (checked 2026-10-12)
Long-term gains in the base Where gains are taxed as ordinary income: net long-term gain less the flat exclusion (never below zero), times the inclusion share. Elsewhere none enters.
New Mexico's values · engine step (compute_state_tax_detail). Sources (Capital gains): Instructions for 2025 PIT-ADJ, Schedule of Additions, Deductions, and Exemptions (checked 2026-10-12); 2025 PIT-ADJ Instructions (checked 2026-10-12); 2025 PIT-1 Instructions (checked 2026-10-12); 2025 Schedule D (Form 1040), Capital Gains and Losses (checked 2026-10-12)
Gains deduction on a separate return married filing separately Married filing separately takes its own (half) flat gains deduction.
New Mexico's values · engine step (compute_state_tax_detail). Sources (Capital gains): Instructions for 2025 PIT-ADJ, Schedule of Additions, Deductions, and Exemptions (checked 2026-10-12); 2025 PIT-ADJ Instructions (checked 2026-10-12); 2025 PIT-1 Instructions (checked 2026-10-12); 2025 Schedule D (Form 1040), Capital Gains and Losses (checked 2026-10-12)
Additional standard deduction at 65 The unmarried amount for a single or head-of-household filer 65 or older, the married amount for each spouse 65 or older, added to the standard deduction before any phase-out.
New Mexico's values · engine step (compute_state_tax_detail). Sources (Deductions, exemptions and credits): Instructions for 2025 PIT-1 New Mexico Personal Income Tax Return (checked 2026-10-12); IRS releases tax inflation adjustments for tax year 2026, including amendments from the One, Big, Beautiful Bill (checked 2026-10-12); HB0252 (checked 2026-09-27); Instructions for 2025 PIT-1 New Mexico Personal Income Tax Return (checked 2026-10-12); Rev. Proc. 2025-32 (2026 inflation adjustments) (checked 2026-10-12); 2025 PIT-RC New Mexico Rebate and Credit Schedule (checked 2026-10-12); 2025 PIT-RC Instructions (checked 2026-10-12); 2025 PIT-ADJ Instructions, Schedule of Additions, Deductions and Exemptions (NM TRD) (checked 2026-10-12)
Additional standard deduction for blindness only when the caller says a person is blind or disabled The unmarried amount for a blind single or head-of-household filer, the married amount for each blind spouse, added to the standard deduction before any phase-out. Age and blindness are separate boxes, so a person 65 or older and blind gets both.
New Mexico's values · engine step (compute_state_tax_detail). Sources (Blindness and disability): 2025 PIT-ADJ instructions (checked 2026-10-12); Rev. Proc. 2025-32 (2026 inflation adjustments) (checked 2026-10-12)
Low- and middle-income exemption At any age, per exemption (the filer, the spouse on a joint return and, where the state counts them, each dependent the caller lists): the amount less the filing status's rate times the income total above its base, not below zero, and none once the income total is over the status's limit.
New Mexico's values · engine step (compute_state_tax_detail). Sources (Deductions, exemptions and credits): Instructions for 2025 PIT-1 New Mexico Personal Income Tax Return (checked 2026-10-12); IRS releases tax inflation adjustments for tax year 2026, including amendments from the One, Big, Beautiful Bill (checked 2026-10-12); HB0252 (checked 2026-09-27); Instructions for 2025 PIT-1 New Mexico Personal Income Tax Return (checked 2026-10-12); Rev. Proc. 2025-32 (2026 inflation adjustments) (checked 2026-10-12); 2025 PIT-RC New Mexico Rebate and Credit Schedule (checked 2026-10-12); 2025 PIT-RC Instructions (checked 2026-10-12); 2025 PIT-ADJ Instructions, Schedule of Additions, Deductions and Exemptions (NM TRD) (checked 2026-10-12)
Dependent exemptions and deductions only when the caller lists dependents An amount per dependent subtracted like the personal exemption: the state's flat amount, or the stepped per-exemption amount the filer gets, or the state's own income steps; nothing above an income limit where there is one; a percentage phase-out per income step where there is one; one more for a dependent in an age band or a student up to an age, for a dependent born in the year, and for a disabled dependent; a deduction per dependent beyond the first on joint and head-of-household returns; and a child deduction by an income table for dependents under an age. A head of household's status exemption that already holds one dependent's amount counts one fewer. Where the state says so, the phase-out is measured on the state AGI (the base before deductions).
New Mexico's values · engine step (compute_state_tax_detail). Sources (Deductions, exemptions and credits): Instructions for 2025 PIT-1 New Mexico Personal Income Tax Return (checked 2026-10-12); IRS releases tax inflation adjustments for tax year 2026, including amendments from the One, Big, Beautiful Bill (checked 2026-10-12); HB0252 (checked 2026-09-27); Instructions for 2025 PIT-1 New Mexico Personal Income Tax Return (checked 2026-10-12); Rev. Proc. 2025-32 (2026 inflation adjustments) (checked 2026-10-12); 2025 PIT-RC New Mexico Rebate and Credit Schedule (checked 2026-10-12); 2025 PIT-RC Instructions (checked 2026-10-12); 2025 PIT-ADJ Instructions, Schedule of Additions, Deductions and Exemptions (NM TRD) (checked 2026-10-12)
Age exemption stepped down by income For each taxpayer at or above the age (each spouse on a joint return): the full amount while the income total is at most the status's start, then less the decrement for each width of income (or part of one) above it; head of household reads the joint column where the state says so. Where the state says so, a blind person qualifies too, with one exemption per person.
New Mexico's values · engine step (compute_state_tax_detail). Sources (Age 65+ subtractions and credits): Instructions for 2025 PIT-ADJ, Schedule of Additions, Deductions, and Exemptions (checked 2026-10-12); Rev. Proc. 2025-32 (2026 inflation adjustments) (checked 2026-10-12)
Income of a person 100 or older At the state's age a person's income is exempt, taken from the base before deductions: all of it for an unmarried filer or a separate return, half the joint income per centenarian spouse on a joint return (the equal-attribution convention; all of it when the household age is used for both). The centenarian does not also take the state's 65-or-older exemption.
New Mexico's values · engine step (compute_state_tax_detail). Sources (Age 65+ subtractions and credits): Instructions for 2025 PIT-ADJ, Schedule of Additions, Deductions, and Exemptions (checked 2026-10-12); Rev. Proc. 2025-32 (2026 inflation adjustments) (checked 2026-10-12)
State taxable income Other ordinary income + Social Security, retirement income, conversion and gains left in the base − standard deduction − personal exemption − age subtractions.
engine step (compute_state_tax_detail). Engine convention, no external source: The order of subtraction follows the state forms; each amount is sourced at its own step.
No tax at or below zero State taxable income at or below zero returns a tax of 0 (credits are not refundable), unless the state has a tax computed apart from taxable income that still applies (next step).
engine step (compute_state_tax_detail). Engine convention, no external source: Every credit the engine carries is nonrefundable, so nothing below can make a zero tax negative; each credit is sourced at its own step.
Separate-return scaling married filing separately For the halved-joint rule, taxable income is doubled before the schedule and the result halved.
New Mexico's values · engine step (compute_state_tax_detail). Sources (Rate schedule): FYI-104 New Mexico Withholding Tax (Rev. 11/2025), wage withholding tables effective January 1, 2026 (checked 2026-10-12); HB0252 (checked 2026-09-27); 2025pit 1 ins (checked 2026-10-12)
The rate schedule Each bracket's rate on the part of taxable income inside it, summed. No rounding: the result is carried in full precision.
New Mexico's values · engine step (apply_state_brackets). Sources (Rate schedule): FYI-104 New Mexico Withholding Tax (Rev. 11/2025), wage withholding tables effective January 1, 2026 (checked 2026-10-12); HB0252 (checked 2026-09-27); 2025pit 1 ins (checked 2026-10-12)
Credits cannot make the tax negative The credits are subtracted and the result floored at zero.
engine step (compute_state_tax_detail). Engine convention, no external source: Every credit the engine carries is nonrefundable; each credit is sourced at its own step.
Qualifying surviving spouse qualifying surviving spouse returns A qualifying surviving spouse (filingStatus qss) is one person on the return, taxed from the single figures with the state's own treatment of the status laid over them: where the state says so, the joint rate schedule, the joint standard deduction, the joint personal exemption, the joint income limits and phase-outs (only those the state sets for joint returns), the married 65+ and blindness amounts, or the head-of-household return; where the state gives the status nothing of its own, the single return. The federal figures the engine derives for the status are the federal qualifying-surviving-spouse ones (the joint standard deduction, the married 65+ amount).
New Mexico's values · engine step (state_tax_effective_config). Sources (Rate schedule): FYI-104 New Mexico Withholding Tax (Rev. 11/2025), wage withholding tables effective January 1, 2026 (checked 2026-10-12); HB0252 (checked 2026-09-27); 2025pit 1 ins (checked 2026-10-12)
Railroad Retirement benefits only when the caller gives Railroad Retirement benefits Railroad Retirement benefits are never taxed by a state (45 U.S.C. §231m). Tier 2 (railroadRetirementTier2) is in the income total the tests use but never in the base. Tier 1 (railroadRetirementTier1) is a part of the gross benefits (socialSecurityGross); its share of the taxable benefits is taken out of the Social Security every state rule sees, so a state that taxes Social Security never reaches it. Where a state's worksheet says so, the benefits reduce a retirement cap or subtraction (ID, IN, MD, ME, MN: both tiers; MI: the taxable railroad benefits); Minnesota's and Utah's Social Security rules test an income without them, Minnesota's, New Jersey's and California's retirement income tests an income without Tier 2; Ohio and Delaware test their own AGI everywhere, which never holds the benefits.
New Mexico's values · engine step (compute_state_tax_detail). Sources (Social Security): Instructions for 2025 PIT-ADJ, Schedule of Additions, Deductions, and Exemptions (checked 2026-10-12); Social Security Income Tax Exemption (checked 2026-10-12)
The capital-loss deduction the state allows With a net capital loss (capitalLoss): the smaller of the loss and the state's limit (the federal $3,000 / $1,500 where the state follows the federal return; MA $2,000, and no more than the interest and dividends); AL the loss less the part carried in, unlimited; PA and NJ none. It comes off the income total the income tests use (and the Social Security worksheets' income); the gross-income filing test (LA) reads the total before it. Engine 1.13.1: with a rental loss (rentalNetIncome below 0, the federal Schedule E line 26 amount) the state allows, the whole loss where the state starts from federal AGI or follows the federal schedule, none in PA and NJ (rental_loss_no_offset): it comes off the same income the same way; a rental profit is other ordinary income.
New Mexico's values · engine step (compute_state_tax_detail). Sources (Capital gains): Instructions for 2025 PIT-ADJ, Schedule of Additions, Deductions, and Exemptions (checked 2026-10-12); 2025 PIT-ADJ Instructions (checked 2026-10-12); 2025 PIT-1 Instructions (checked 2026-10-12); 2025 Schedule D (Form 1040), Capital Gains and Losses (checked 2026-10-12)
Each spouse's own Social Security joint returns On a joint return, each spouse's own Social Security is the spouse's share of the benefits by spouse.socialSecurityGross when the caller gives it (Tier 1 railroad benefits left out), else half each. It is what the per-spouse rules read: Colorado's per-spouse subtraction, Rhode Island's per-spouse modification, and the Maine, Maryland and other retirement caps reduced by the benefits each spouse received (with each spouse's own railroad benefits where the state counts them).
New Mexico's values · engine step (compute_state_tax_detail). Sources (Social Security): Instructions for 2025 PIT-ADJ, Schedule of Additions, Deductions, and Exemptions (checked 2026-10-12); Social Security Income Tax Exemption (checked 2026-10-12)
Medical expense deduction (NJ) and exemption (NM) NJ: the medical expenses over a share of New Jersey gross income (line 29); NM: $3,000 when the filer or spouse is 65 or older and the medical care expenses are at least $28,000 (not on a separate return); off income.
New Mexico's values · engine step (st_compute). Sources (Deductions, exemptions and credits): Instructions for 2025 PIT-1 New Mexico Personal Income Tax Return (checked 2026-10-12); IRS releases tax inflation adjustments for tax year 2026, including amendments from the One, Big, Beautiful Bill (checked 2026-10-12); HB0252 (checked 2026-09-27); Instructions for 2025 PIT-1 New Mexico Personal Income Tax Return (checked 2026-10-12); Rev. Proc. 2025-32 (2026 inflation adjustments) (checked 2026-10-12); 2025 PIT-RC New Mexico Rebate and Credit Schedule (checked 2026-10-12); 2025 PIT-RC Instructions (checked 2026-10-12); 2025 PIT-ADJ Instructions, Schedule of Additions, Deductions and Exemptions (NM TRD) (checked 2026-10-12)
Refundable state credits The credits paid beyond the tax (reported in refundableCredits; netTax = totalTax less them): earned income credits as a share of the federal EIC with each state's own age band (OK on the 2020 federal credit, DC's own childless schedule, the CalEITC table, MN's Working Family Credit), the NYC EIC and school tax credits, and the property-tax, renter, grocery and senior credits of MA, MI, NJ, ID, HI, NM, OK, AZ, NY, RI, WV, ME, DC, MN, MO, WI, IN and MT, each on its own income measure. Engine 1.13.1: a part-year NYC resident's school tax credits (the Table 2 proration chart and the rate-reduction amount on IT-360.1 line 47; IT-203 lines 60 / 60a for a part-year state resident).
New Mexico's values · engine step (state_tax_refundable_credits). Sources (Deductions, exemptions and credits): Instructions for 2025 PIT-1 New Mexico Personal Income Tax Return (checked 2026-10-12); IRS releases tax inflation adjustments for tax year 2026, including amendments from the One, Big, Beautiful Bill (checked 2026-10-12); HB0252 (checked 2026-09-27); Instructions for 2025 PIT-1 New Mexico Personal Income Tax Return (checked 2026-10-12); Rev. Proc. 2025-32 (2026 inflation adjustments) (checked 2026-10-12); 2025 PIT-RC New Mexico Rebate and Credit Schedule (checked 2026-10-12); 2025 PIT-RC Instructions (checked 2026-10-12); 2025 PIT-ADJ Instructions, Schedule of Additions, Deductions and Exemptions (NM TRD) (checked 2026-10-12)

Rate schedule

Single

Taxable income from	to	Rate
$0	$5,500	1.5%
$5,500	$16,500	3.2%
$16,500	$33,500	4.3%
$33,500	$66,500	4.7%
$66,500	$210,000	4.9%
$210,000	and up	5.9%

Married filing jointly

Taxable income from	to	Rate
$0	$8,000	1.5%
$8,000	$25,000	3.2%
$25,000	$50,000	4.3%
$50,000	$100,000	4.7%
$100,000	$315,000	4.9%
$315,000	and up	5.9%

Head of household

Taxable income from	to	Rate
$0	$8,000	1.5%
$8,000	$25,000	3.2%
$25,000	$50,000	4.3%
$50,000	$100,000	4.7%
$100,000	$315,000	4.9%
$315,000	and up	5.9%

Married filing separately: the engine computes the MFJ tax on twice the income and halves it, which is the same as halving every MFJ threshold and the MFJ deduction.

Source review notes (what the sources do not state outright, or what the engine does not carry):

No fetchable official page lists the statutory 2026 bracket thresholds verbatim: the NM T&RD 'Personal Income Tax Rates' page renders its table client-side (no values in the HTML), the PIT-1 rate tables (page 1T) are not in the instructions PDF, and nmlegis.gov (HB252) and Justia (NMSA 7-2-7) return HTTP 403 to the checker. Intermediate thresholds (16,500/33,500/66,500 single; 25,000/50,000/100,000 MFJ) are therefore corroborated only through the withholding bases and the top-bracket base amounts.

FYI-104 New Mexico Withholding Tax (Rev. 11/2025), wage withholding tables effective January 1, 2026, New Mexico Taxation and Revenue Department. New Mexico's 2026 percentage-method withholding tables apply the six statutory rates 1.5%, 3.2%, 4.3%, 4.7%, 4.9% and 5.9%; the top-bracket base amounts ($9,748 single, $14,624 married and head of household) equal the tax the engine's 2026 single and MFJ schedules produce at $210,000 and $315,000, and the head-of-household table uses the married base amounts. Checked 2026-10-12.
HB0252, nmlegis.gov (archived copy). nmlegis.gov: "A. For married individuals filing joint returns, heads of household and surviving spouses:" Checked 2026-09-27.
2025pit 1 ins, New Mexico Taxation and Revenue Department. New Mexico Taxation and Revenue Department: "enter the allowable federal standard deduction from federal Form 1040 or 1040SR, line 12" Checked 2026-10-12.

Deductions, exemptions and credits

Standard deduction (or the exemption the engine carries in its place): $16,100 single, $32,200 married filing jointly, $24,150 head of household.
The standard deduction includes $2,050 more for a single or head-of-household filer 65 or older, and $1,650 more for each spouse 65 or older on a married return.
Low- and middle-income exemption, at any age: $2,500 per exemption (the filer, and the spouse on a joint return), less 15% (single), 10% (head of household), 10% (MFJ) or 20% (married filing separately) of federal adjusted gross income above $20,000, $30,000, $30,000 and $15,000; none once that income is over $36,667, $55,000, $55,000 and $27,500. Each dependent the caller lists is an exemption too.

Instructions for 2025 PIT-1 New Mexico Personal Income Tax Return, New Mexico Taxation and Revenue Department. New Mexico taxable income subtracts the federal standard deduction the filer claimed on federal Form 1040 line 12, so the New Mexico standard deduction equals the federal amount. Engine 1.7.0: PIT-1 line 13: $4,000 per dependent beyond the first on a joint or head-of-household return; the §7-2-5.8 exemption counts every dependent (PIT-1 line 5). Earned income credit (engine 1.12.0, refundableCredits): the Working Families Tax Credit, 25% of the federal EIC. Checked 2026-10-12.
IRS releases tax inflation adjustments for tax year 2026, including amendments from the One, Big, Beautiful Bill, Internal Revenue Service. The 2026 federal standard deduction is $16,100 single, $32,200 married filing jointly and $24,150 head of household. Checked 2026-10-12.
HB0252, nmlegis.gov (archived copy). nmlegis.gov: "A. For married individuals filing joint returns, heads of household and surviving spouses:" Checked 2026-09-27.
Instructions for 2025 PIT-1 New Mexico Personal Income Tax Return, New Mexico Taxation and Revenue Department. The New Mexico low- and middle-income exemption (PIT-1 line 14, NMSA 7-2-5.8): $2,500 per exemption less 15% (single) / 10% (joint, head of household) / 20% (married filing separately) of federal AGI above $20,000 / $30,000 / $30,000 / $15,000, for AGI up to $36,667 / $55,000 / $55,000 / $27,500. Checked 2026-10-12.
Rev. Proc. 2025-32 (2026 inflation adjustments), Internal Revenue Service. For 2026 the federal additional standard deduction for a taxpayer 65 or older is $2,050 unmarried and $1,650 married; New Mexico's deduction is the federal one. Checked 2026-10-12.
2025 PIT-RC New Mexico Rebate and Credit Schedule, New Mexico Taxation and Revenue Department. Low Income Comprehensive Tax Rebate (engine 1.12.0): PIT-RC Table 1 by modified gross income and exemptions. Checked 2026-10-12.
2025 PIT-RC Instructions, New Mexico Taxation and Revenue Department. Low Income Comprehensive Tax Rebate (engine 1.12.0): PIT-RC Table 1 by modified gross income and exemptions. Property tax rebate for persons 65 or older (engine 1.12.0): PIT-RC section 3. Medical care credit for persons 65 or older (engine 1.12.0): $2,800 with $28,000 or more of unreimbursed medical care expenses. Medical care credit (engine 1.12.0): $2,800 ($1,400 each on separate returns). Checked 2026-10-12.
2025 PIT-ADJ Instructions, Schedule of Additions, Deductions and Exemptions (NM TRD). Medical care expense exemption (engine 1.12.0): $3,000 when the filer or spouse is 65 or older with $28,000 or more of unreimbursed medical care expenses. Checked 2026-10-12.

Age 65+ subtractions and credits

An exemption of up to $8,000 for each taxpayer 65 or older (each spouse on a joint return): in full while federal adjusted gross income is at most $18,000 (single), $30,000 (MFJ and head of household) or $15,000 (married filing separately), then $1,000 less for each $1,500 (single and married filing separately) or $3,000 (joint column) of income, or part of it, above those points, until it is gone.

Instructions for 2025 PIT-ADJ, Schedule of Additions, Deductions, and Exemptions, New Mexico Taxation and Revenue Department. The exemption for persons 65 or older (or blind), PIT-ADJ line 13 and Table 1: up to $8,000 per qualifying taxpayer (each spouse on a joint return), $1,000 less per $3,000 of federal AGI above $30,000 (joint, head of household, surviving spouse) or per $1,500 above $18,000 (single) / $15,000 (married filing separately); nothing above $51,000 / $28,500 / $25,500. Engine 1.8.0: PIT-ADJ line 12 exempts the income of a person 100 or older (unmarried or a separate return: all of it; a joint return: half the joint income per centenarian spouse, the engine's equal attribution of community income), and a centenarian does not also take the line 13 exemption. Checked 2026-10-12.
Rev. Proc. 2025-32 (2026 inflation adjustments), Internal Revenue Service. For 2026 the federal additional standard deduction for a taxpayer 65 or older is $2,050 unmarried and $1,650 married, which New Mexico's deduction (the federal one) carries. Checked 2026-10-12.

Social Security

Exempt when income is at or below $100,000 (single), $75,000 (married filing separately) and $150,000 (married filing jointly and head of household). Above the threshold the whole federally taxable amount is included (a cliff, not a phase-out).

API value: socialSecurityRule: "full_above_threshold". The engine's input is the federally taxable amount; income tests use the sum of the income components as the adjusted-gross-income proxy.

Instructions for 2025 PIT-ADJ, Schedule of Additions, Deductions, and Exemptions, New Mexico Taxation and Revenue Department. All Social Security income included in federal AGI is exempt when federal AGI does not exceed $100,000 (single), $75,000 (married filing separately) or $150,000 (married filing jointly, head of household, surviving spouse); above the threshold no part is exempt. Checked 2026-10-12.
Social Security Income Tax Exemption, New Mexico Taxation and Revenue Department. The Social Security exemption is available to single filers under $100,000 of income, joint filers, surviving spouses and heads of household under $150,000, and married-separate filers under $75,000. Checked 2026-10-12.

IRA, 401(k) and private pensions

No exclusion: pension, annuity and IRA/401(k) distributions are taxed as ordinary income.

Instructions for 2025 PIT-1 New Mexico Personal Income Tax Return, New Mexico Taxation and Revenue Department. New Mexico starts from federal AGI (PIT-1 line 9), so taxable IRA, 401(k) and private-pension distributions are taxed at the regular rates; the only general age-based relief is the income-limited $8,000 exemption for filers 65+ (PIT-ADJ line 13), and a person 100 or older exempts their income (line 12). Checked 2026-10-12.
Instructions for 2025 PIT-ADJ, Schedule of Additions, Deductions, and Exemptions, New Mexico Taxation and Revenue Department. New Mexico's only broad retirement-age relief is an exemption of up to $8,000 for filers 65 or older or blind that phases out with income; there is no pension or IRA exclusion. Checked 2026-10-12.

Public pensions

No separate treatment: public pensions follow the rules for other retirement income above.

Instructions for 2025 PIT-1 New Mexico Personal Income Tax Return, New Mexico Taxation and Revenue Department. Government pensions are part of federal AGI (PIT-1 line 9) and New Mexico has no general public-pension subtraction, so they are taxed like other pensions (armed-forces retirement pay has a separate $30,000 exemption, PIT-ADJ line 24). Checked 2026-10-12.

Military retirement pay

Military retirement pay is exempt up to $30,000 per taxpayer.
Military pay the military rule does not exempt is pension income under the general retirement rules.
Rules are applied per taxpayer at that person's own age when the spouse's age is given. API value: rules.militaryRetirement.treatment: "capped_exclusion".

2025pit adj ins, New Mexico Taxation and Revenue Department. Up to $30,000 of armed forces retirement pay is exempt per qualifying retiree; each spouse on a joint return who qualifies claims their own. Checked 2026-10-12.

Roth conversions

A conversion is taxed as ordinary income in full. It does not draw any retirement-income exclusion.

Instructions for 2025 PIT-1 New Mexico Personal Income Tax Return, New Mexico Taxation and Revenue Department. A traditional-to-Roth conversion is taxable income in federal AGI, which is the New Mexico starting point (PIT-1 line 9); no New Mexico subtraction applies, so it is taxed as ordinary income. Checked 2026-10-12.

Capital gains

Net long-term gain is taxed as ordinary income.
The first $2,500 of gain is excluded.
Short-term gains are ordinary income.

Source review notes (what the sources do not state outright, or what the engine does not carry):

The 40%-of-up-to-$1,000,000 New Mexico business-sale alternative is out of scope (engine models portfolio gains only).

Instructions for 2025 PIT-ADJ, Schedule of Additions, Deductions, and Exemptions, New Mexico Taxation and Revenue Department. Net capital gain is taxed as ordinary income after a deduction of the greater of 100% of net capital gain up to $2,500 or 40% of up to $1,000,000 of gain from selling a New Mexico business; the engine applies the $2,500 alternative. Checked 2026-10-12.
2025 PIT-ADJ Instructions, New Mexico Taxation and Revenue Department. Married individuals filing separately may each claim only half of the $2,500 net capital gains deduction allowed on a joint return ($1,250). Checked 2026-10-12.
2025 PIT-1 Instructions, New Mexico Taxation and Revenue Department. The state return starts from federal adjusted gross income (federal taxable income in CO, IA, ND), so the federal capital-loss deduction (up to $3,000, $1,500 married filing separately) and its carryover are in the state base (engine 1.9.0: cap_loss_limit). Checked 2026-10-12.
2025 Schedule D (Form 1040), Capital Gains and Losses, Internal Revenue Service. The federal return deducts a net capital loss up to $3,000 ($1,500 married filing separately) on Form 1040 line 7a; a state that starts from federal adjusted gross income or federal taxable income carries that deduction. Checked 2026-10-12.

Blindness and disability

The standard deduction includes $2,050 more for a blind single or head-of-household filer and $1,650 more for each blind spouse on a married return. Age and blindness are separate: a person 65 or older and blind gets both amounts.
The age exemption above also goes to a blind person under that age; a person who is both gets it once.
The API applies these through its blind, disabled, spouse.blind and spouse.disabled fields; absent means false.

2025 PIT-ADJ instructions, New Mexico Taxation and Revenue Department. The exemption for persons 65 or older also goes to a blind person, one per person. Checked 2026-10-12.
Rev. Proc. 2025-32 (2026 inflation adjustments), Internal Revenue Service. The federal additional standard deduction for 2026, per condition (age 65 and blindness each count): $2,050 unmarried, $1,650 married. The state takes it where its deduction is the federal one. Checked 2026-10-12.

Part-year and nonresident returns

Part-year resident (PIT-B): the tax a full-year resident would owe on all the year's income, times the state's income ratio.
Nonresident (PIT-B): the tax a full-year resident would owe on all the year's income, times the state's income ratio.
The ratio: the federal AGI of the state's income over the federal AGI of the whole year, rounded to 6 places, at most 1.
A nonresident's retirement income is not taxable by the state (4 U.S.C. §114); the API refuses it in residency.stateIncome. The credit for tax paid to another state and the earned income credits on these returns are not computed.

Married couples whose residency differs (engine 1.13.0)

With residency.spouse on a joint request, each allowed treatment is calculated and reported in residency.couple; tax is the required one, else the state's default, else the couple's residency.election, else the joint return the request's mfj names. Each rule is quoted from the state's instructions (engine 1.14.0: and its statutes, regulations, bulletins and other official guidance) in the sources below.

Spouses	New Mexico's rule
One spouse a full-year resident, the other a part-year resident	a joint part-year / nonresident return is required.
One spouse a full-year resident, the other a nonresident	a joint part-year / nonresident return is required.
One spouse a part-year resident, the other a nonresident	a joint part-year / nonresident return is required.
Both part-year residents, different resident periods	a joint part-year / nonresident return is required.
Both nonresidents, only one with income from the state	a joint part-year / nonresident return is required.

Instructions for 2025 PIT-B, Schedule of New Mexico Allocation and Apportionment of Income, New Mexico Taxation and Revenue Department. Part-year / nonresident return (engine 1.12.0, residency): Checked 2026-10-12.
2025 PIT-B New Mexico Allocation and Apportionment of Income Schedule, New Mexico Taxation and Revenue Department. Part-year / nonresident return (engine 1.12.0, residency): Checked 2026-10-12.
2025 PIT-1 Personal Income Tax Return Instructions, New Mexico Taxation and Revenue Department. Part-year / nonresident return (engine 1.12.0, residency): Checked 2026-10-12.
2025 PIT-ADJ Instructions, New Mexico Taxation and Revenue Department. Part-year / nonresident return (engine 1.12.0, residency): Checked 2026-10-12.
2025 PIT-1 Personal Income Tax Return Instructions, New Mexico Taxation and Revenue Department. Married couples whose residency differs (engine 1.13.0): Checked 2026-10-12.
Instructions for 2025 PIT-B, Schedule of New Mexico Allocation and Apportionment of Income, New Mexico Taxation and Revenue Department. Married couples whose residency differs (engine 1.13.0): Checked 2026-10-12.

Worked examples

Computed by the engine for the fixed households below (the same ones for every state, so states compare directly). Federal tax is not supplied, so a federal-tax deduction is not taken; the income tests use the sum of the components as income.

Household (engine inputs)	State tax
Single, 67: $30,000 private pension, $20,000 IRA, $10,000 interest, $24,000 Social Security ($17,000 federally taxable), $5,000 long-term gain	$1,675.45
Married filing jointly, 70: $40,000 public pension, $40,000 IRA, $20,000 interest, $40,000 Social Security ($34,000 federally taxable), $10,000 long-term gain	$2,773
Single, 60: $60,000 other ordinary income and a $50,000 Roth conversion	$4,059.10
Married filing jointly, 66: $30,000 IRA, a $40,000 Roth conversion, $30,000 Social Security ($25,500 federally taxable)	$1,072.50
Single, 58: $36,000 military retirement pay and $30,000 wages	$580.70
Married filing jointly, ages 67 and 61: $50,000 IRA, $10,000 interest, $30,000 Social Security ($25,500 federally taxable), each spouse's age given	$713.45

Line by line

The intermediate lines the engine records while it computes each example (its detail record, printed as it comes out; lines that are zero are left out). The engine's documentation build checks that the lines add up to the taxable income and the tax, for every state, filing status and a grid of households. Each line links the engine step that produces it.

Single, 67: $30,000 private pension, $20,000 IRA, $10,000 interest, $24,000 Social Security ($17,000 federally taxable), $5,000 long-term gain: $1,675.45

Line	Amount
Income total used by the income tests	$82,000
+ Other ordinary income in the base	$10,000
+ Retirement income in the base	$50,000
+ Long-term gain in the base	$2,500
− Standard deduction	$18,150
= State taxable income	$44,350
Tax from the rate schedule	$1,675.45
= Tax before credits	$1,675.45
= Tax	$1,675.45

Married filing jointly, 70: $40,000 public pension, $40,000 IRA, $20,000 interest, $40,000 Social Security ($34,000 federally taxable), $10,000 long-term gain: $2,773

Line	Amount
Income total used by the income tests	$144,000
+ Other ordinary income in the base	$20,000
+ Retirement income in the base	$80,000
+ Long-term gain in the base	$7,500
− Standard deduction	$35,500
= State taxable income	$72,000
Tax from the rate schedule	$2,773
= Tax before credits	$2,773
= Tax	$2,773

Single, 60: $60,000 other ordinary income and a $50,000 Roth conversion: $4,059.10

Line	Amount
Income total used by the income tests	$110,000
+ Other ordinary income in the base	$60,000
+ Roth conversion in the base	$50,000
− Standard deduction	$16,100
= State taxable income	$93,900
Tax from the rate schedule	$4,059.10
= Tax before credits	$4,059.10
= Tax	$4,059.10

Married filing jointly, 66: $30,000 IRA, a $40,000 Roth conversion, $30,000 Social Security ($25,500 federally taxable): $1,072.50

Line	Amount
Income total used by the income tests	$95,500
+ Retirement income in the base	$30,000
+ Roth conversion in the base	$40,000
− Standard deduction	$35,500
= State taxable income	$34,500
Tax from the rate schedule	$1,072.50
= Tax before credits	$1,072.50
= Tax	$1,072.50

Single, 58: $36,000 military retirement pay and $30,000 wages: $580.70

Line	Amount
Income total used by the income tests	$66,000
Military pay excluded (not in the base)	$30,000
+ Other ordinary income in the base	$30,000
+ Retirement income in the base	$6,000
− Standard deduction	$16,100
= State taxable income	$19,900
Tax from the rate schedule	$580.70
= Tax before credits	$580.70
= Tax	$580.70

Married filing jointly, ages 67 and 61: $50,000 IRA, $10,000 interest, $30,000 Social Security ($25,500 federally taxable), each spouse's age given: $713.45

Line	Amount
Income total used by the income tests	$85,500
+ Other ordinary income in the base	$10,000
+ Retirement income in the base	$50,000
− Standard deduction	$33,850
= State taxable income	$26,150
Tax from the rate schedule	$713.45
= Tax before credits	$713.45
= Tax	$713.45

After 2026: how the amounts move

A request with projection (API) estimates a later tax year from these rules: every dollar amount and age test below moves the way New Mexico's law moves it. Rates and the rules themselves stay the 2026 ones (how projection works).

Amounts (engine fields)	After 2026	What the law says, and the source
`brackets_single` (the single rate schedule's thresholds), `brackets_mfj` (the mfj rate schedule's thresholds), `brackets_hoh` (the hoh rate schedule's thresholds)	Fixed in law: held at the rules-year amount in every later year.	The six-bracket schedules apply for tax years on or after January 1, 2025 with nominal amounts; § 7-2-7 contains no inflation adjustment. NMSA 1978 § 7-2-7 (Chapter 7, Taxation - NMOneSource) (New Mexico Compilation Commission (NMOneSource), statute): Rate schedules, no indexing provision. Quoted: "Not over $8,000 1.5% of taxable income Over $8,000 but not over $25,000 $120 plus 3.2% of excess over $8,000"; "Not over $5,500 1.5% of taxable income Over $5,500 but not over $16,500 $82.50 plus 3.2% of excess over $5,500". Checked 2026-10-12.
`std_deduction_single`, `std_deduction_mfj`, `std_deduction_hoh`, `std_deduction_aged_add_unmarried`, `std_deduction_aged_add_married`, `blind_std_add_unmarried`, `blind_std_add_married`	Tied to an indexed federal amount: federal standard deduction under IRC 63(c) and the IRC 63(f) additional amounts for age/blindness, indexed by the IRC 1(f)(3) C-CPI-U cost-of-living adjustment; the increase rounded down to a multiple of $50.	New Mexico net income excludes the standard deduction allowed by IRC 63 for the taxable year, so it is the federal basic standard deduction plus the IRC 63(f) aged/blind amounts, indexed federally (increases rounded down to $50). NMSA 1978 § 7-2-2 (Chapter 7, Taxation - NMOneSource) (New Mexico Compilation Commission (NMOneSource), statute): Definition of net income adopts the IRC 63 standard deduction. Quoted: "an amount equal to the standard deduction allowed the taxpayer for the taxpayer's taxable year by Section 63 of the Internal Revenue Code". Checked 2026-10-12. 26 U.S.C. 63 (Taxable income defined) (Legal Information Institute (Cornell) - U.S. Code, federal): IRC 63(c)(4) indexes the basic standard deduction and the subsection (f) additional amounts for age and blindness by the IRC 1(f)(3) cost-of-living adjustment. Quoted: "each dollar amount contained in paragraph (2)(B), (2)(C), or (5) or subsection (f) shall be increased by an amount equal to". Checked 2026-10-12. 26 U.S.C. 1 (Tax imposed), subsection (f)(7) (Legal Information Institute (Cornell) - U.S. Code, federal): IRC 1(f)(7)(A): increases under 1(f)(2)(A) (brackets), 63(c)(4) (standard deduction) and 151(d)(4) are rounded down to a multiple of $50. Quoted: "section 63(c)(4), section 68(b)(2) [1] or section 151(d)(4) is not a multiple of $50, such increase shall be rounded to the next lowest multiple of $50". Checked 2026-10-12.
`ss_exempt_agi_single`, `ss_exempt_agi_mfj`, `ss_exempt_agi_mfs`	Fixed in law: held at the rules-year amount in every later year.	The Social Security exemption AGI limits ($100,000 single, $150,000 joint/HOH, $75,000 MFS) are nominal in § 7-2-5.14; no inflation adjustment. NMSA 1978 § 7-2-5.14 (Chapter 7, Taxation - NMOneSource) (New Mexico Compilation Commission (NMOneSource), statute): States the limits. Quoted: "seventy-five thousand dollars ($75,000) for married individuals filing separate returns; B. one hundred fifty thousand dollars ($150,000) for heads of household". Checked 2026-10-12.
`cg_flat_exclusion`, `cg_flat_exclusion_mfs`	Fixed in law: held at the rules-year amount in every later year.	The net capital gain deduction is capped at $2,500 (half for MFS) in § 7-2-34; no inflation adjustment. NMSA 1978 § 7-2-34 (Chapter 7, Taxation - NMOneSource) (New Mexico Compilation Commission (NMOneSource), statute): States the cap and MFS half. Quoted: "but not to exceed two thousand five hundred dollars ($2,500)"; "may each claim only one-half of the deduction provided by this section". Checked 2026-10-12.
`military_cap`	Fixed in law: held at the rules-year amount in every later year.	The armed forces retirement pay exemption is $30,000 per retiree in current § 7-2-5.13 (the 2022 version's 2024-2026 schedule was replaced by a flat amount without end date); no inflation adjustment. NMSA 1978 § 7-2-5.13 (Chapter 7, Taxation - NMOneSource) (New Mexico Compilation Commission (NMOneSource), statute): States the flat $30,000. Quoted: "may claim an exemption in an amount equal to thirty thousand dollars ($30,000) of armed forces retirement pay". Checked 2026-10-12.
`senior_step_exemption`, `senior_step_agi_single`, `senior_step_agi_mfj`, `senior_step_agi_mfs`, `senior_step_width_single`, `senior_step_width_mfj`, `senior_step_width_mfs`, `senior_step_decrement`	Fixed in law: held at the rules-year amount in every later year.	The age 65+/blind exemption (up to $8,000, stepping down $1,000 per $1,500/$3,000 of AGI over $18,000 single / $30,000 joint / $15,000 MFS) is a nominal table in § 7-2-5.2 effective since 1987; no inflation adjustment. NMSA 1978 § 7-2-5.2 (Chapter 7, Taxation - NMOneSource) (New Mexico Compilation Commission (NMOneSource), statute): States the table. Quoted: "not to exceed eight thousand dollars ($8,000) of income"; "Not over $30,000 Over $30,000 but not over $33,000"; "Not over $18,000 Over $18,000 but not over $19,500". Checked 2026-10-12.
`senior_step_min_age`	Attained age: the same age in every year.	Fixed attained age: sixty-five years of age or older. NMSA 1978 § 7-2-5.2 (Chapter 7, Taxation - NMOneSource) (New Mexico Compilation Commission (NMOneSource), statute): Age wording. Quoted: "Any individual sixty-five years of age or older". Checked 2026-10-12.
`lmi_exemption`, `lmi_agi_limit_single`, `lmi_agi_limit_mfj`, `lmi_agi_limit_hoh`, `lmi_agi_limit_mfs`, `lmi_base_single`, `lmi_base_mfj`, `lmi_base_hoh`, `lmi_base_mfs`	Fixed in law: held at the rules-year amount in every later year.	The low- and middle-income exemption ($2,500 per federal exemption, reduced above $20,000/$30,000/$15,000 and ending at $36,667/$55,000/$27,500) is nominal in § 7-2-5.8; no inflation adjustment. NMSA 1978 § 7-2-5.8 (Chapter 7, Taxation - NMOneSource) (New Mexico Compilation Commission (NMOneSource), statute): States the amounts. Quoted: "multiplied by two thousand five hundred dollars ($2,500) of income"; "For single individuals with adjusted gross income up to thirty-six thousand six hundred sixty-seven dollars ($36,667)"; "surviving spouses or for heads of households with adjusted gross income up to fifty-five thousand dollars ($55,000)". Checked 2026-10-12.
`dep_after_first_deduction`	Fixed in law: held at the rules-year amount in every later year.	$4,000 per dependent beyond the first (joint/HOH) while the federal personal exemption amount is zero; nominal in § 7-2-39, no inflation adjustment. NMSA 1978 § 7-2-39 (Chapter 7, Taxation - NMOneSource) (New Mexico Compilation Commission (NMOneSource), statute): States the $4,000. Quoted: "the product of four thousand dollars ($4,000) multiplied by the difference between the number of dependents claimed on the taxpayer's return and one". Checked 2026-10-12.
`centenarian_min_age`	Attained age: the same age in every year.	Fixed attained age: income of a person 100 years of age or older (not a dependent) is exempt. NMSA 1978 § 7-2-5.7 (Chapter 7, Taxation - NMOneSource) (New Mexico Compilation Commission (NMOneSource), statute): Age wording. Quoted: "who is one hundred years of age or older and who is not a dependent of another individual is exempt from state income tax". Checked 2026-10-12.
`cap_loss_limit`, `cap_loss_limit_mfs`	Fixed in law: held at the rules-year amount in every later year.	New Mexico starts from federal AGI, so the fixed IRC 1211(b) limit applies. 26 U.S.C. 1211 (Limitation on capital losses) (Legal Information Institute (Cornell) - U.S. Code, federal): IRC 1211(b) limits a non-corporate capital loss against other income to $3,000 ($1,500 MFS), with no inflation adjustment. Quoted: "(1) $3,000 ($1,500 in the case of a married individual filing a separate return), or". Checked 2026-10-12.
`nm-credits` (a table held in code)	Fixed in law: held at the rules-year amount in every later year.	NMSA 7-2-14 and 7-2-18 set the LICTR and the property tax rebate tables, 7-2-18.13 the $2,800 medical care credit; no indexing clause. 2025 PIT-RC New Mexico Rebate and Credit Schedule (New Mexico Taxation and Revenue Department, agency_page): Low Income Comprehensive Tax Rebate (PIT-RC Section 2) Quoted: "$36,000 or less may qualify for the low income comprehensive tax rebate (Section 2)"; "$16,000 or less who are age 65 or older may qualify for the property tax rebate (Section 3)". Checked 2026-10-12. 2025 PIT-RC Instructions (New Mexico Taxation and Revenue Department, agency_page): Low Income Comprehensive Tax Rebate (PIT-RC Section 2) Quoted: "Table 1. 2025 Low-Income Comprehensive Tax Rebate Table". Checked 2026-10-12. 2025 PIT-RC New Mexico Rebate and Credit Schedule (New Mexico Taxation and Revenue Department, agency_page): Property Tax Rebate for persons 65 or older (PIT-RC Section 3) Quoted: "$36,000 or less may qualify for the low income comprehensive tax rebate (Section 2)"; "$16,000 or less who are age 65 or older may qualify for the property tax rebate (Section 3)". Checked 2026-10-12. 2025 PIT-RC Instructions (New Mexico Taxation and Revenue Department, agency_page): Property Tax Rebate for persons 65 or older (PIT-RC Section 3) Quoted: "cannot exceed $250 or, for a married taxpayer filing"; "LINE 16c. Multiply line 16a by 0.06, and enter the product". Checked 2026-10-12. 2025 PIT-RC Instructions (New Mexico Taxation and Revenue Department, agency_page): Refundable Medical Care Credit for persons 65 or older (PIT-RC line 23) Quoted: "penses of $28,000 or more during tax year 2025, you may"; "claim a tax credit of $2,800.". Checked 2026-10-12.
`med_exemption`, `med_exemption_floor`	Fixed in law: held at the rules-year amount in every later year.	NMSA 7-2-5.10 (PIT-ADJ line 18): the $3,000 exemption and the $28,000 of expenses are dollar amounts with no adjustment clause: fixed in law. Instructions for 2025 PIT-ADJ (New Mexico Taxation and Revenue Department, instructions): Line 18. Quoted: "be eligible to claim an exemption of $3,000.". Checked 2026-10-12.
`med_exemption_min_age`	Attained age: the same age in every year.	Fixed attained age: 65 years of age or older (the filer or spouse). Instructions for 2025 PIT-ADJ (New Mexico Taxation and Revenue Department, instructions): Line 18 age wording. Quoted: "If you or your spouse are 65 years of age or older, and you". Checked 2026-10-12.

Enacted for later years, not applied by the projection

None found: the research found no change enacted for years after 2026 beyond the schedules above.

What the engine does not calculate, and known approximations

The 40% deduction for gain on the sale of a New Mexico business is not modeled.
Tax is the exact rate schedule on taxable income; the PIT-TRT table (midpoint of $100 rows, whole dollars) differs by at most $2.95 below $100,000, and above $100,000 its bases are $2.00 ($2.50 MFS) below the statutory schedule.
The child income tax credit is refundable, and the child day care and special-needs adoption credits need expenses or certification; none is calculated. Sources: Instructions for 2025 PIT-1 New Mexico Personal Income Tax Return (checked 2026-10-12); IRS releases tax inflation adjustments for tax year 2026, including amendments from the One, Big, Beautiful Bill (checked 2026-10-12); HB0252 (checked 2026-09-27); Instructions for 2025 PIT-1 New Mexico Personal Income Tax Return (checked 2026-10-12); Rev. Proc. 2025-32 (2026 inflation adjustments) (checked 2026-10-12); 2025 PIT-RC New Mexico Rebate and Credit Schedule (checked 2026-10-12); 2025 PIT-RC Instructions (checked 2026-10-12); 2025 PIT-ADJ Instructions, Schedule of Additions, Deductions and Exemptions (NM TRD) (checked 2026-10-12).
The medical care expense exemption (PIT-ADJ line 18) is not given on a married-filing-separately return: the instructions do not say how separate filers share it. medicalExpenses is read as the household's unreimbursed medical care expenses, insurance premiums included, as the exemption and the medical care credit count them. Sources: Instructions for 2025 PIT-ADJ, Schedule of Additions, Deductions, and Exemptions (checked 2026-10-12); Rev. Proc. 2025-32 (2026 inflation adjustments) (checked 2026-10-12).

What the engine does not calculate for any state (itemized deductions, credits beyond those listed, part-year residents, and more) is listed on the calculation order page.

Verification

Worksheet-tested 22 scenarios in backend/tests/test_state_worksheets_3.c replay the TY2025 PIT-1, PIT-ADJ and PIT-TRT line by line (2026 federal standard deduction substituted) through the JSON API.

Golden scenarios (hand-computed expected tax, asserted to within $1): M11, M12, G26-NM-HOH, G26-NM-CG.
State-specific unit tests: test_credit_programs_1, test_compute_federal_ss_parts, test_military_tiers, test_military_per_return_caps, test_hoh_federal_deduction_states, test_nm_aged_step_and_lmi_exemptions, test_blind_with_age.
Structural tests covering every state: 9.
State forms and worksheets followed in the test derivations: PIT-1 lines 9, 12, 14, 15, 17 and 18; PIT-1 line 14 worksheet (low- and middle-income exemption); PIT-ADJ line 13 Table 1 (65 or older), line 16 (net capital gains), line 24 (armed forces retirement), line 25 Table 2 (Social Security); PIT-TRT tax rate table (midpoint rows) and its over-$100,000 schedule.