In our 510,000-path Monte Carlo study of 30-year retirement outcomes, Massachusetts retirees finished at 73.42% success rate (ranked #32 of 51 by success rate, #31 of 51 by lowest median lifetime state tax). Median 30-year state-tax cost: $63,000 — that is $63,000 more than a Wyoming retiree pays. Median terminal balance after 30 years: $866,823. State tax is part of the optimization here — the playbook below shows the federal-state-ACA stack.
The MA verdict
For a retiree planning withdrawals in 2026, Massachusetts is one of the higher-burden states for retirees, especially on traditional pre-tax withdrawals. One flat bracket plus a millionaire surcharge above the surtax threshold, and a $2m estate exemption.
Massachusetts reaches 9.00% only above $1,107,750 of taxable income: a 5.00% bracket rate plus a 4.00% surcharge on the excess. Every dollar figure on this page uses the 5.00% bracket rate, because a conversion of the sizes modelled here never reaches that threshold.
Massachusetts has no dollar-capped retirement-income exclusion, so every converted dollar enters the state tax base. The marginal cost of a conversion here is the federal bracket plus the state rate plus, below 65, whatever premium tax credit crossing the 400% FPL cliff would cost you.
Worked example: $30k Roth conversion in Massachusetts
Consider a married couple age 58 in Massachusetts with $75,000 of taxable income, both on ACA Marketplace coverage. They want to convert $30,000 from a traditional IRA to a Roth. The Massachusetts state tax on that conversion is approximately $1,500 — the full amount is taxed at 5.00%. 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 $84,600 — they lose their full ACA premium tax credit, roughly $12,000. Total cost of the $30,000 conversion: about $20,100, or an effective 67.0% marginal rate. Massachusetts applies one rate to all taxable income, so that state figure is the full amount before any deduction Massachusetts allows. The federal-state-ACA stack matters in Massachusetts.
Cost breakdown
| Component | Amount |
|---|---|
| Federal income tax (22% bracket) | $6,600 |
| Massachusetts state income tax | $1,500 |
| ACA premium tax credit clawback | $12,000 |
| Total cost on $30,000 conversion | $20,100 (67.0% effective) |
Scenario B (high-tax): cliff-protective $15k conversion in Massachusetts
A Massachusetts couple aged 58 with $66K MAGI, both on a Silver-tier Marketplace plan converts only $15,000 because crossing the 400% FPL cliff in Massachusetts layers state tax, federal tax at 22%, AND a ~$12,000 PTC clawback on top of each other. State tax on $15k: $750 — the full amount is taxed at 5.00%. Federal tax: $3,300. PTC preserved. Effective rate: 27.0%. In a high-tax state, the optimization is small annual conversions over many years — never a single 'big year' if Marketplace coverage is in play.
What the Monte Carlo data says about Massachusetts
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 Massachusetts compared to the best- and worst-case states:
| Metric | Massachusetts | Wyoming (best) | California (worst) |
|---|---|---|---|
| 30-year success rate | 73.42% | 77.11% | 69.03% |
| Rank (of 51) | #32 | #1 | #51 |
| Median lifetime state tax (30y) | $63,000 | $0 | $154,980 |
| Median total tax (30y) | $281,400 | $218,400 | $373,380 |
| Median terminal balance | $866,823 | $999,751 | $695,612 |
| Δ success vs Wyoming | -3.69 pp | — | −8.08 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. Massachusetts's row in the dataset uses the same portfolio + spend + retirement age as every other state — the only variable is state tax treatment.
How Massachusetts treats capital gains in retirement
Massachusetts taxes long-term capital gains as ordinary income at the same top bracket rate (5.00%). 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 up to 5.00% 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 Massachusetts
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. Massachusetts'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:
- Household of 1: $62,600
- Household of 2: $84,600
- Household of 3: $106,600
- Household of 4: $128,600
Optimal Roth conversion strategy for Massachusetts
The MA-specific playbook depends on tier:
- 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.
- Stay under the cliff if you can. In Massachusetts at 5.00%, 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.
- 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.
- Coordinate with capital gains and the 0% LTCG bracket. Massachusetts taxes long-term capital gains as ordinary income at the same top bracket rate (5.00%). 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 up to 5.00% at the state level — meaningful in this jurisdiction, particularly during Roth-conversion years when your MAGI is already elevated.
- Plan ahead for IRMAA. The IRMAA Medicare premium surcharge has a 2-year lookback. A Massachusetts 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 Massachusetts retirees
| Question | Massachusetts |
|---|---|
| State income tax | 9.00% top marginal |
| Number of brackets | 1 |
| Social Security taxed | No |
| 401(k) / Traditional IRA taxed | Yes |
| Retirement-income exclusion (couple) | None |
| Roth conversion draws that exclusion | Not applicable |
| State estate / inheritance tax | Yes |
| Retirement-friendliness tier | high tax |
| Notable feature | one flat bracket plus a millionaire surcharge above the surtax threshold, and a $2M estate exemption |
| 30-yr MC success rate (rank) | 73.42% (#32/51) |
| Median 30-yr state tax | $63,000 |
Model your full Massachusetts 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.
Run a free simulation →Related calculators and reading
- All-states retirement tax comparison — see Massachusetts alongside the other 50 jurisdictions.
- State Retirement Tax Data 2026 — the per-jurisdiction rate, exclusion and Social Security figures behind this page, as CSV and JSON.
- ACA Subsidy Cliff Optimizer — find the largest Roth conversion that keeps you under 400% FPL.
- Roth Conversion Optimizer — bracket-fill vs. fixed-amount strategy comparison.
- RMD + IRMAA Calculator — Medicare premium surcharge based on 2-year-old MAGI.
- Safe Withdrawal Rate Calculator — sequence-of-returns-aware withdrawal planning.
- Research: 51-State 30-year Monte Carlo (2026) — full ranking and dataset.
- Research: Monte Carlo ACA Cliff 2026 — 80,000-path study of the cliff cost.
FAQ
Does Massachusetts tax Roth conversions?
Massachusetts taxes Roth conversions as ordinary income at the state level. A $30,000 conversion by a couple aged 58 costs about $1,500 in state tax alone — the full amount is taxed at 5.00% — on top of federal tax and any ACA subsidy clawback. Massachusetts applies one rate to all taxable income, so that state figure is the full amount before any deduction Massachusetts allows.
What is Massachusetts's 30-year Monte Carlo retirement success rate?
In QuantCalc's 510,000-path Monte Carlo study, a representative retiree in Massachusetts (age 60, $2M balance, 60/40 portfolio, $80K real spend) finished 30 years at 73.42% success rate — ranked #32 of 51 jurisdictions. Median 30-year state tax: $63,000. Median terminal balance: $866,823.
What is the ACA cliff in Massachusetts 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 — $84,600. Crossing it by even $1 of MAGI eliminates the full subsidy under the OBBBA 2026 rules.
Is Massachusetts a good state to retire for tax purposes?
Massachusetts is one of the higher-burden states for retirees, especially on traditional pre-tax withdrawals. One flat bracket plus a millionaire surcharge above the surtax threshold, and a $2m estate exemption. In our Monte Carlo ranking it placed #32 of 51 jurisdictions.
Does Massachusetts tax Social Security benefits?
No — Massachusetts does not tax Social Security benefits at the state level, at any income level.
Does Massachusetts tax 401(k) and IRA withdrawals?
Yes — Massachusetts taxes 401(k) and traditional IRA withdrawals as ordinary income, at a top bracket rate of 5.00%.
Does Massachusetts have a state estate or inheritance tax?
Yes — Massachusetts has a state-level estate or inheritance tax in addition to the federal estate tax. Plan transfers accordingly.
How does Massachusetts tax capital gains?
Massachusetts taxes long-term capital gains as ordinary income at the same top bracket rate (5.00%). 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 up to 5.00% at the state level — meaningful in this jurisdiction, particularly during Roth-conversion years when your MAGI is already elevated.
Last updated 2026-08-23. State income tax figures reflect the 2026 schedule published by Massachusetts's tax authority. 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.