Filling the 12% bracket with Roth conversions (2026)
By Mario Bailey · Published · Last reviewed
Bracket filling means converting exactly enough traditional IRA balance to reach the top of a chosen bracket and no further. The 2026 numbers below are taken from the same IRS Rev. Proc. data the calculator uses. All figures are taxable income: gross income minus your deduction.
The 12% bracket in 2026
| Filing status | Bracket starts | Bracket ends | Standard deduction | Approx. AGI at ceiling |
|---|---|---|---|---|
| Single | $12,400 | $50,400 | $16,100 | $66,500 |
| Married filing jointly | $24,800 | $100,800 | $32,200 | $133,000 |
| Married filing separately | $12,400 | $50,400 | $16,100 | $66,500 |
| Head of household | $17,700 | $67,450 | $24,150 | $91,600 |
What filling it costs
A conversion that runs floor to ceiling is taxed at exactly 12% by construction; the table prices the full fill for each filing status. One dollar past the ceiling is taxed at 22%, a 10-point step, which is the entire argument for stopping at the line rather than a round number.
| Filing status | Bracket width (taxable income) | Tax to fill it all at 12% |
|---|---|---|
| Single | $38,000 | $4,560 |
| Married filing jointly | $76,000 | $9,120 |
| Married filing separately | $38,000 | $4,560 |
| Head of household | $49,750 | $5,970 |
Conversion room at common income levels
Room to the top of the 12% bracket from a given taxable income. When the income sits below the bracket floor, the room shown spans lower brackets first: a conversion crossing bracket boundaries is taxed at each bracket's rate in sequence, not all at 12%. Zero means that income already sits past the bracket ceiling.
| Taxable income | Single | Married filing jointly | Married filing separately | Head of household |
|---|---|---|---|---|
| $50,000 | $400 | $50,800 | $400 | $17,450 |
| $100,000 | $0 | $800 | $0 | $0 |
| $150,000 | $0 | $0 | $0 | $0 |
| $250,000 | $0 | $0 | $0 | $0 |
IRMAA proximity
For a standard-deduction filer, MAGI at the top of the 12% bracket stays below the first IRMAA threshold for every filing status. Pension, Social Security, or investment income on top of the conversion can still push past it.
- Single: first IRMAA threshold $109,000 MAGI; bracket-ceiling MAGI approx. $66,500 (below the first tier)
- Married filing jointly: first IRMAA threshold $218,000 MAGI; bracket-ceiling MAGI approx. $133,000 (below the first tier)
- Married filing separately: first IRMAA threshold $109,000 MAGI; bracket-ceiling MAGI approx. $66,500 (below the first tier)
- Head of household: first IRMAA threshold $109,000 MAGI; bracket-ceiling MAGI approx. $91,600 (below the first tier)
The ACA cliff, if you convert before 65
Marketplace premium tax credits end above 400% of the federal poverty level, a cliff rather than a phase-out, and for a standard-deduction filer that line sits below this bracket's ceiling for at least one filing status. Filling the 12% bracket while on marketplace coverage forfeits the entire credit for the year. The lines below use the 2025-vintage poverty guidelines that govern 2026 coverage under IRC §36B(d)(3)(B).
- Single: 400% line $62,600 MAGI; bracket-ceiling MAGI approx. $66,500 (over the cliff)
- Married filing jointly: 400% line $84,600 MAGI; bracket-ceiling MAGI approx. $133,000 (over the cliff)
- Married filing separately: 400% line $62,600 MAGI; bracket-ceiling MAGI approx. $66,500 (over the cliff)
- Head of household: 400% line $84,600 MAGI; bracket-ceiling MAGI approx. $91,600 (over the cliff)
The cliff guide works the dollar cost, including the one-dollar crossing that forfeits a four-figure credit.
FAQ
Where does the 12% bracket end in 2026 for married filing jointly?
At $100,800 of taxable income. Add the standard deduction to translate that into gross income.
Can filling the 12% bracket trigger IRMAA?
Generally no: for a standard-deduction filer, MAGI at the bracket ceiling (taxable income plus standard deduction, the Approx. AGI column above) stays below the first IRMAA threshold for every filing status. Other income can still change that.
What does it cost to fill the whole 12% bracket in 2026?
The bracket spans $38,000 of taxable income for single filers, which is $4,560 of tax at 12%, and $76,000 for married filing jointly ($9,120). Starting below the floor costs less per dollar, since the slices in lower brackets are taxed at their own rates.