QuantCalcState TaxMissouri

Missouri Retirement Tax 2026: Roth Conversion + ACA Cliff Strategy

4.70% top marginal rate. Ss exempt regardless of income (2024 reform), public pension exclusion. Model the federal + state + ACA stack in one place.

In our 510,000-path Monte Carlo study of 30-year retirement outcomes, Missouri retirees finished at 73.41% success rate (ranked #33 of 51 by success rate, #26 of 51 by lowest median lifetime state tax). Median 30-year state-tax cost: $59,220 — that is $59,220 more than a Wyoming retiree pays. Median terminal balance after 30 years: $859,032. State tax is part of the optimization here — the playbook below shows the federal-state-ACA stack.

Top rate: 4.70% Brackets: 9 Taxes SS: No Taxes 401(k)/IRA: Yes Estate tax: No MC rank: #33/51

The MO verdict

For a retiree planning withdrawals in 2026, Missouri is a middle-of-the-road state for retirement taxation. Ss exempt regardless of income (2024 reform), public pension exclusion.

There is meaningful state tax on Roth conversions, but the rate is not punitive. Modeling the joint federal + state + ACA cliff cost matters — small conversions can be efficient, large conversions less so.

Live ACA cliff check

The 400% FPL cliff is a federal threshold, but the dollars at stake depend on your county's benchmark Silver premium. Adjust the inputs below — every result is computed in your browser, no data is sent to QuantCalc.

Worked example: $30k Roth conversion in Missouri

Consider a married couple age 58 in Missouri with $75,000 of taxable income, both on ACA Marketplace coverage. They want to convert $30,000 from a traditional IRA to a Roth. At Missouri's 4.70% top marginal rate, the state tax on that conversion is approximately $1,410. Federal tax at the 22% bracket adds another $6,600. And because the conversion pushes their MAGI to $105,000 — over the 400% FPL cliff of $81,760 — they lose their full ACA premium tax credit, roughly $12,000. Total cost of the $30,000 conversion: about $20,010, or an effective 66.7% marginal rate. The federal-state-ACA stack matters in Missouri.

Cost breakdown

ComponentAmount
Federal income tax (22% bracket)$6,600
Missouri state income tax$1,410
ACA premium tax credit clawback$12,000
Total cost on $30,000 conversion$20,010 (66.7% effective)

Scenario B (moderate): cliff-aware $40k conversion in Missouri

A Missouri couple aged 60, both on Marketplace coverage with $50K wages converts $40,000 but stops at exactly the 400% FPL cliff to preserve their PTC. State tax at 4.70% effective ~4.00%: $1,598. Federal tax at 22%: $8,800. ACA PTC preserved. Total cost: $10,398, or 26.0% effective. In moderate-tax states, the conversion size is bounded by both the IRMAA two-year lookback and the ACA cliff — not state tax alone.

What the Monte Carlo data says about Missouri

QuantCalc Research ran a 30-year, 10,000-path Monte Carlo simulation for an identical representative retiree (age 60, $2M starting balance, 60/40 portfolio, $80K real annual spend) in each of the 51 U.S. jurisdictions. Here's how Missouri compared to the best- and worst-case states:

MetricMissouriWyoming (best)California (worst)
30-year success rate73.41%77.07%67.91%
Rank (of 51)#33#1#51
Median lifetime state tax (30y)$59,220$0$167,580
Median total tax (30y)$277,620$218,400$385,980
Median terminal balance$859,032$996,189$652,555
Δ success vs Wyoming-3.66 pp−9.16 pp

Sources: QuantCalc 51-State Monte Carlo Study (2026-05-12) — 510,000 total paths, methodology fully documented and dataset released CC-BY-4.0. Missouri's row in the dataset uses the same portfolio + spend + retirement age as every other state — the only variable is state tax treatment.

How Missouri treats capital gains in retirement

Missouri taxes long-term capital gains as ordinary income at the same top marginal rate (4.70%). That stacks on top of federal LTCG (0%/15%/20%) and the 3.8% NIIT for high earners. A 'free' federal 0% LTCG harvest still costs you 4.70% at the state level — meaningful in this jurisdiction, particularly during Roth-conversion years when your MAGI is already elevated.

Why the ACA cliff hits hard in Missouri

The 400% federal-poverty-level cliff is federal, not state-specific — but its dollar impact depends on the benchmark Silver-plan premium in your county. Missouri's Marketplace pricing and your household composition determine the size of the subsidy at risk. A two-person household near 400% FPL can easily have $10,000–$15,000 of annual premium tax credit on the line. Under the OBBBA 2026 restoration of the cliff, $1 of additional MAGI above 400% FPL eliminates the entire credit.

For 2026 the 400% FPL threshold is:

Optimal Roth conversion strategy for Missouri

The MO-specific playbook depends on tier:

  1. Identify your cliff distance. Compute MAGI from all income sources (wages, capital gains, interest, dividends, traditional withdrawals). Find your headroom under 400% FPL. Use the live cliff widget above for a quick check.
  2. Stay under the cliff if you can. In Missouri at 4.70%, the marginal cost of going over the cliff is federal tax + state tax + full PTC clawback. The break-even conversion size is smaller than in tax-free states.
  3. If you must go over, convert big. Once you've crossed the cliff, additional conversion dollars only cost federal + state tax (no incremental PTC loss). A "rip the bandage" conversion year can be efficient if you have many traditional dollars to move.
  4. Coordinate with capital gains and the 0% LTCG bracket. Missouri taxes long-term capital gains as ordinary income at the same top marginal rate (4.70%). That stacks on top of federal LTCG (0%/15%/20%) and the 3.8% NIIT for high earners. A 'free' federal 0% LTCG harvest still costs you 4.70% at the state level — meaningful in this jurisdiction, particularly during Roth-conversion years when your MAGI is already elevated.
  5. Plan ahead for IRMAA. The IRMAA Medicare premium surcharge has a 2-year lookback. A Missouri resident in their early 60s converting today will see IRMAA implications at 65. See RMD + IRMAA calculator for the lookback math.

State tax basics for Missouri retirees

QuestionMissouri
State income tax4.70% top marginal
Number of brackets9
Social Security taxedNo
401(k) / Traditional IRA taxedYes
State estate / inheritance taxNo
Retirement-friendliness tiermoderate
Notable featureSS exempt regardless of income (2024 reform), public pension exclusion
30-yr MC success rate (rank)73.41% (#33/51)
Median 30-yr state tax$59,220

Model your full Missouri retirement scenario

Free 10,000-path Monte Carlo with state-specific tax engine, ACA cliff, Roth conversion optimizer, IRMAA lookback — all in your browser, no signup.

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Related calculators and reading

FAQ

Does Missouri tax Roth conversions?

Missouri taxes Roth conversions as ordinary income at the state level. At a top marginal rate of 4.70%, a $30,000 conversion costs about $1,410 in state tax alone — on top of federal tax and any ACA subsidy clawback.

What is Missouri's 30-year Monte Carlo retirement success rate?

In QuantCalc's 510,000-path Monte Carlo study, a representative retiree in Missouri (age 60, $2M balance, 60/40 portfolio, $80K real spend) finished 30 years at 73.41% success rate — ranked #33 of 51 jurisdictions. Median 30-year state tax: $59,220. Median terminal balance: $859,032.

What is the ACA cliff in Missouri for 2026?

The ACA premium-tax-credit cliff is a federal threshold, not state-specific. For a household of two in 2026, it sits at 400% of the federal poverty level — $81,760. Crossing it by even $1 of MAGI eliminates the full subsidy under the OBBBA 2026 rules.

Is Missouri a good state to retire for tax purposes?

Missouri is a middle-of-the-road state for retirement taxation. Ss exempt regardless of income (2024 reform), public pension exclusion. In our Monte Carlo ranking it placed #33 of 51 jurisdictions.

Does Missouri tax Social Security benefits?

Missouri does not tax Social Security benefits at the state level.

Does Missouri have a state estate or inheritance tax?

No — Missouri does not impose a state-level estate or inheritance tax.

How does Missouri tax capital gains?

Missouri taxes long-term capital gains as ordinary income at the same top marginal rate (4.70%). That stacks on top of federal LTCG (0%/15%/20%) and the 3.8% NIIT for high earners. A 'free' federal 0% LTCG harvest still costs you 4.70% at the state level — meaningful in this jurisdiction, particularly during Roth-conversion years when your MAGI is already elevated.

Last updated 2026-05-16. State income tax data sourced from the Missouri Department of Revenue and the Tax Foundation's 2026 state tax facts publication. ACA poverty-level figures from HHS 2026 Federal Register. Monte Carlo numbers from the QuantCalc 51-state research drop (2026-05-12, CC-BY-4.0). This page is educational. Not tax, legal, or financial advice — consult a qualified advisor.