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Barista FIRE — part-time wages + ACA subsidy feedback

Part-time work covers some of your spending, so the portfolio you need shrinks — but the wages raise your MAGI, and MAGI drives the ACA premium tax credit. This projection solves that loop as a fixed point under 2026 law, where the enhanced credits have expired and the 400% FPL cliff is back: one dollar of MAGI over the line forfeits the whole credit. Part-time W-2 taxes and account-type gross-up are in the math, and the answer is always a range.

HHS poverty guidelines · asOf 2025-01 IRS Rev. Proc. 2025-25 · asOf 2025-07 IRS Rev. Proc. 2025-32 · asOf 2025-10 KFF benchmark premiums · asOf 2026-01 Updated 2026-07-06

Legislative uncertainty — 2026 subsidies are a moving target

The enhanced (ARPA/IRA) premium tax credit expired 2025-12-31, restoring the original §36B schedule — including the 400% FPL cliff — for 2026. The US House passed a three-year extension on 2026-01-08, but the Senate has not. If an extension becomes law retroactively, the cliff would disappear and every subsidy figure here would change. Treat all 2026 credit amounts as projections under current law, not settled numbers.

Assumptions

live · solves the MAGI→subsidy loop
Everything you spend in a year except marketplace premiums — the engine adds those itself.
Gross pay before tax. Federal income tax and FICA (6.2% + 1.45% + 0.9% additional) are computed on it.
Filing status
Sets the standard deduction, brackets, and FICA additional-Medicare threshold.
Tax-household size — it sets the poverty-guideline line your MAGI is measured against (48 states + DC).
Adults on marketplace coverage
Enrollees buying the benchmark plan. Child rates are not modeled (v1).
21–64. Premiums are age-rated up to 3:1 on the CMS default curve; 65+ is Medicare territory, outside this model.
Withdrawals come from
Traditional: 100% ordinary income and 100% MAGI. Taxable: only the realized-gain slice is income (LTCG). Roth: adds nothing to MAGI — the cliff cannot see it.
Only used for the taxable account: the fraction of each sale that is gain (rest is basis). Long-held positions run higher.
The projection band runs ±0.5pp around this rate. A sensitivity illustration, not an endorsement of any rate.
Set your inputs to solve the MAGI → subsidy → withdrawal loop.
$—
Gross withdrawal — Net premium — Cliff headroom — ▲ —
Required portfolio at your rate Withdrawal-rate band (±0.5pp)
Set your inputs — this rolls the portfolio need across a sweep of part-time wages, not one guess. Taxes and the ACA cliff both bite, so the honest answer is a range, not a single number.

Required portfolio range

low · typical · high

Coral = low bound (withdrawal rate +0.5pp), green = typical at your rate, lime = high bound (rate −0.5pp). A withdrawal-rate sensitivity band, not market percentiles.

The 2026 ACA cliff, live

net premium vs MAGI · 400% FPL marker

Net annual premium as MAGI rises. The vertical jump is the 400% FPL cliff: one dollar past it forfeits the entire projected credit.

— Federal tax + FICA / yr
— Projected credit / gross benchmark
Methodology & sources
Show the math ›
Run the projection to see the worked numbers for your inputs.
Assumptions & sources ›
AssumptionValueSource · asOf
Poverty guideline (FPL) 2025 guidelines, 48 states + DC HHS ASPE · asOf 2025-01 · applies to coverage year 2026 per IRC §36B(d)(3)(B); Alaska/Hawaii use higher lines not modeled
Applicable percentage 2.10%–9.96% of MAGI, 400% cliff IRS Rev. Proc. 2025-25 · asOf 2025-07 · post-enhancement schedule; linear interpolation within brackets
Benchmark (SLCSP) premium $625/mo national average, age 40 KFF marketplace benchmark averages · asOf 2026-01 · rescaled by the CMS default age curve (21→1.0, 40→1.278, 64→3.0); illustrative — the real SLCSP varies by rating area
Federal brackets + deduction 2026 tables, single / MFJ IRS Rev. Proc. 2025-32 · asOf 2025-10 · standard deduction only; no credits or itemizing
LTCG stacking 0/15/20% above ordinary income IRS Rev. Proc. 2025-32 §2.03 · asOf 2025-10 · taxable-account gains stack on top of wages
FICA 6.2% + 1.45% (+0.9%) SSA 2026 wage base $184,500 · asOf 2025-10 · employee side; wages only, never withdrawals
Withdrawal-rate band typical ±0.5pp structural sensitivity around your input — an illustration, not a sustainability claim; sequence-of-returns risk is not simulated here (v1)
State taxes not modeled federal only (v1); state income tax and state-specific subsidy programs vary widely

Below 100% FPL the model shows zero credit — in expansion states that is Medicaid territory (to 138% FPL), which has no premium at all; in non-expansion states it can be a coverage gap. ACA MAGI also counts untaxed Social Security and tax-exempt interest, which this v1 does not model. Every subsidy figure is a projection under 2026 current law.

Written by Author to be finalized before launch · Updated 2026-07-06

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