Read the map before moving income
Income definitions vary. This is where mistakes happen.
Quick reference: 2026 federal cliff table
Click a column heading to sort. Dollar values are 2026 tax year unless the row states a different coverage or lookback year.
| What changes when crossed | Cost of crossing by $1 | Income definition | Lookback / timing | ||||
|---|---|---|---|---|---|---|---|
| Social Security taxation: first tier | $25,000 | $32,000 | Up to 50% of benefits become taxable as provisional income rises. | Can add 50 cents of taxable income per extra $1 before the 85% tier. | ╱ | PROV AGI + tax-exempt interest + 1/2 SS | Current tax year; thresholds are unindexed. |
| Social Security taxation: 85% tier | $34,000 | $44,000 | Up to 85% of benefits can become taxable. | Often adds 85 cents of taxable income per extra $1 until capped. | ╱ | PROV | Current tax year; thresholds are unindexed since 1983/1993 law. |
| Saver's Credit: 50% to 20% | $24,250 | $48,500 | Credit rate falls from 50% to 20% of eligible retirement contributions. | For a $2,000 contribution, a $1 crossing can lose $600 of credit. | ┃ | AGI | Current tax year. |
| Saver's Credit: 20% to 10% | $26,250 | $52,500 | Credit rate falls from 20% to 10%. | For a $2,000 contribution, crossing can lose $200 of credit. | ┃ | AGI | Current tax year. |
| Saver's Credit: 10% to 0% | $40,250 | $80,500 | Credit disappears above the upper limit. | For a $2,000 contribution, crossing can lose $200 of credit. | ┃ | AGI | Current tax year. |
| Capital gains 0% bracket | $49,450 taxable income | $98,900 taxable income | Long-term gains/qualified dividends above the line enter the 15% band. | Positive cliff: fill the 0% band; the next $1 of gain costs $0.15. | + | Taxable income after ordinary-income stacking | Current tax year. |
| ACA premium tax credit 400% FPL cliff | $63,840 household size 1 | $132,000 household size 4 | Above 400% FPL, no federal PTC under current 2026 law. | Varies by age/ZIP; can be the full subsidy. A $24,000 benchmark for a family of four would lose about $10,853 at $132,001. | ┃ | FPL household income MAGI variant | 2026 coverage; reconciled on Form 8962. |
| Enhanced senior deduction | $75,000 MAGI | $150,000 MAGI | 2025-2028 extra $6,000 per age-65+ taxpayer phases down. | 6% deduction loss per extra $1; tax cost depends on bracket. | ╱ | MAGI | Current tax year; temporary through 2028. |
| AOTC / Lifetime Learning Credit phase-out | $80,000-$90,000 | $160,000-$180,000 | Education credits phase out over the range. | AOTC can lose up to $2,500 per eligible student across a $10k/$20k band. | ╱ | MAGI | Current tax year. |
| Student-loan interest deduction | $85,000-$100,000 | $175,000-$205,000 | Up to $2,500 deduction phases out. | Deduction shrinks roughly $0.167 per $1 single, $0.083 per $1 MFJ. | ╱ | MAGI | Current tax year. |
| IRMAA I: Medicare B + D | > $109,000 | > $218,000 | Adds Part B $81.20/mo + Part D $14.50/mo per person. | $1 over costs $1,148.40/yr per person; $2,296.80/yr for two Medicare spouses. | ┃ | MAGI AGI + tax-exempt interest | Two-year lookback: 2026 uses 2024 MAGI. |
| IRMAA II | > $137,000 | > $274,000 | Part B IRMAA rises to $202.90/mo; Part D to $37.50/mo. | Incremental $1,736.40/yr per person versus tier I. | ┃ | MAGI | Two-year lookback. |
| Roth IRA direct contribution phase-out | $153,000-$168,000 | $242,000-$252,000 | Direct Roth contribution limit phases out. | Usually not a tax cost if backdoor Roth is clean; watch pro-rata IRA balances. | ╱ | MAGI Roth IRA MAGI | Current tax year. |
| Traditional IRA deduction: active participant | $81,000-$91,000 | $129,000-$149,000 | Deductible IRA contribution phases out when covered by a workplace plan. | Deduction loss depends on bracket; backdoor strategy may be cleaner. | ╱ | MAGI IRA MAGI | Current tax year. |
| EE/I savings-bond education exclusion | $101,800-$116,800 | $152,650-$182,650 | Interest exclusion for qualified higher education phases out. | Cost is excluded interest becoming taxable over the range. | ╱ | MAGI | Current tax year. |
| Additional Medicare Tax | $200,000 | $250,000 | 0.9% extra Medicare tax on wages/self-employment above threshold. | $0.009 per extra wage dollar. | ╱ | Medicare wages / SE income | Current tax year; employer withholds above $200k wages regardless of filing status. |
| Net Investment Income Tax | $200,000 | $250,000 | 3.8% tax on lesser of net investment income or MAGI above threshold. | Up to $0.038 per extra investment-income dollar. | ╱ | MAGI | Current tax year; thresholds are statutory, not indexed. |
| Qualified Business Income 199A thresholds | $201,750-$276,750 | $403,500-$553,500 | Wage/property limits and SSTB restrictions phase in. | Can reduce or erase the 20% QBI deduction; varies by business facts. | ╱ | Taxable income before QBI deduction | Current tax year. |
| Child Tax Credit / ODC phase-out | $200,000 | $400,000 | $2,200 CTC per child and $500 ODC reduce by $50 per $1,000 or fraction over threshold. | A $1 crossing can lose $50 because the rule rounds up to the next $1,000. | ┃ | MAGI | Current tax year. |
| IRMAA III | > $171,000 | > $342,000 | Part B IRMAA rises to $324.60/mo; Part D to $60.40/mo. | Incremental $1,735.20/yr per person versus tier II. | ┃ | MAGI | Two-year lookback. |
| IRMAA IV | > $205,000 | > $410,000 | Part B IRMAA rises to $446.30/mo; Part D to $83.30/mo. | Incremental $1,735.20/yr per person versus tier III. | ┃ | MAGI | Two-year lookback. |
| Adoption credit / assistance | $265,080-$305,080 | $265,080-$305,080 | $17,670 credit/exclusion phases out. | Up to $17,670 lost over a $40,000 band. | ╱ | MAGI | Current tax year. |
| IRMAA V | ≥ $500,000 | ≥ $750,000 | Part B IRMAA rises to $487.00/mo; Part D to $91.00/mo. | Incremental $580.80/yr per person versus tier IV. | ┃ | MAGI | Two-year lookback. |
| Earned Income Tax Credit taper | Phase-out often starts $23,890 | Phase-out starts $31,160 for 1+ kids | Maximum 2026 credit: $664 no children, $4,427 one, $7,316 two, $8,231 three+. | For MFJ with two children, losing $7,316 over $31,160-$65,899 is about 21.1% before payroll/ACA effects. | ╱ | AGI or earned income, whichever is greater | Current tax year. |
| Social Security earnings test before FRA | $24,480 | Per worker | Before FRA, benefits withheld $1 per $2 above limit; FRA year has $65,160 limit and $1 per $3 rule. | Not a permanent tax: benefits are recomputed at FRA, but cash flow drops now. | ╱ | Wages / net self-employment earnings | 2026 earnings before full retirement age. |
| FAFSA SAI assessment bands | Parent AAI bands begin around -$8,900 and $22,600 | Family-size dependent | Parent adjusted available income is assessed from 22% to 47%; student income often 50%; student assets 20%. | Not a tax bill, but aid eligibility can fall sharply where income/assets are assessed. | ╱ | FAFSA formula income/assets | 2027-28 aid year uses prior-prior tax data. |
| Medicaid / CHIP eligibility cliffs | State and category specific | State and category specific | Federal structure, state thresholds, expansion status, and child/adult categories determine eligibility. | Can be a full coverage loss; must check state rules. | ┃ | FPL program-specific MAGI | Coverage year; state rules change. |
The five cliffs that move real money
┃ IRMAA brackets: the $1-over Medicare surcharge
Definition: IRMAA is an income-related monthly adjustment amount added to Medicare Part B and Part D premiums when modified AGI crosses statutory brackets.
Worked example: A married couple on Medicare has 2024 MAGI of $218,001 after a December Roth conversion. In 2026, both spouses enter IRMAA tier I: ($81.20 Part B + $14.50 Part D) x 12 x 2 = $2,296.80 of extra annual premium for crossing by $1.
Moves: size Roth conversions to the bracket edge; use QCDs after age 70 1/2 for charity; keep muni interest in the IRMAA MAGI add-back; file SSA-44 after retirement, marriage, divorce, death of spouse, work reduction, or employer-pension loss.
Gotcha: the bill arrives two years later. The first Medicare year can be priced by income from the last working years.
┃ ACA subsidy cliff: 400% FPL is back for 2026
1 person$132,000
family 4
Definition: the premium tax credit uses household income as a percentage of FPL. For 2026, IRS guidance again caps eligibility at not more than 400% FPL.
Worked example: A 48-state family of four has 2026 FPL of $33,000, so 400% FPL is $132,000. At 400%, the expected contribution can be 9.96%, or $13,147.20. If their benchmark plan is $24,000/year, the PTC is $10,852.80; at $132,001, the PTC is $0.
Moves: HSA contributions, pre-tax retirement contributions, timing freelance invoices, and realizing gains in a different year can protect the line. Tax-loss harvesting helps only if it lowers MAGI in the coverage year.
Gotcha: reconciliation happens on Form 8962. An optimistic income estimate can become a full repayment problem at filing time.
╱ Social Security tax torpedo
Definition: Social Security taxation uses provisional income, not AGI: AGI plus tax-exempt interest plus half of Social Security benefits.
Worked example: A couple receives $48,000 of Social Security and withdraws $30,000 from an IRA. Provisional income is $54,000. Taxable SS is $6,000 + 85% x ($54,000 - $44,000) = $14,500. Another $1,000 IRA withdrawal can add $1,850 to taxable income before the cap, so a 12% bracket behaves like 22.2%.
Moves: fill low brackets before benefits start, use Roth assets to bridge high-torpedo years, and model QCDs once eligible.
Gotcha: municipal-bond interest is tax-free for ordinary income but still counts in provisional income and IRMAA MAGI.
+ Capital gains 0% bracket: the good cliff
Definition: long-term capital gains stack on top of ordinary taxable income; the 0% rate applies only until taxable income reaches the 0% ceiling.
Worked example: A married couple has $60,000 ordinary income and takes the $32,200 standard deduction. Ordinary taxable income is $27,800. They can harvest $98,900 - $27,800 = $71,100 of long-term gains at 0% federal tax.
Moves: harvest gains in sabbatical, early-retirement, or low-income years; coordinate with ACA and IRMAA before selling.
Gotcha: 0% capital gains still increase AGI/MAGI and can poison ACA subsidies, IRMAA, FAFSA, and credit phase-outs.
╱ EITC and stacked benefit tapers
Definition: the Earned Income Tax Credit rises, plateaus, then tapers using AGI or earned income, whichever is greater.
Worked example: For a 2026 married couple with two qualifying children, EITC is $7,316 and phases out from $31,160 to $65,899. The taper is $7,316 / $34,739 = 21.1%. Add 7.65% employee payroll tax and a 12% bracket, and the visible marginal rate can exceed 40% before ACA, SNAP, childcare, or housing effects.
Moves: claim every above-the-line deduction you actually qualify for; avoid end-of-year surprises; use VITA/free filing help for refundable-credit accuracy.
Gotcha: investment income over $12,200 disqualifies EITC for 2026, even if earned income is otherwise eligible.
The toolkit: manage MAGI without managing your life around pennies
Convert up to the next bracket or IRMAA line, then stop. Example: if 2024 MFJ IRMAA buffer is $9,400, convert $9,300, not "about $10k."
A qualified charitable distribution can satisfy charitable intent without increasing AGI, making it cleaner for IRMAA than an itemized cash gift.
2026 HSA limits are $4,400 self-only and $8,750 family, plus $1,000 catch-up at 55+; these can lower ACA MAGI.
Bonuses, RSU sales, freelance invoices, and capital gains often have timing flexibility. Use it near true cliffs.
Gain harvesting is excellent under the 0% line, dangerous near ACA/IRMAA. Loss harvesting helps if it lowers current-year AGI.
Itemized charitable deductions can reduce taxable income but usually do not reduce AGI/MAGI. They do not save an IRMAA crossing.
Anti-moves
Ordinary tax brackets are slopes. Only the next dollar is taxed at the higher rate.
Spending $1,000 of planning effort to avoid a $50 phase-out is a bad trade.
IRMAA, FPL, EITC, capital-gain brackets, IRA limits, and credit thresholds change annually.
Where slopes pile up
Route A: 67-year-old couple, SS + IRA
The statutory 12% or 22% bracket understates the lived rate when each $1 of IRA income also makes more Social Security taxable and then hits IRMAA two years later.
Route B: family of four, EITC + CTC + ACA
Payroll tax, EITC taper, child-credit rounding, ACA reconciliation, and state benefits can stack. This is a planning case, not a reason to reject durable income gains.
Common mistakes
IRMAA adds tax-exempt interest. ACA adds untaxed Social Security, tax-exempt interest, and foreign excluded income. Education credits have their own add-backs.
A 2024 conversion can raise 2026 Medicare premiums. The appeal exists, but ordinary investment income is not a life-changing event.
"Convert a round number" is how people cross a cliff. Compute the bracket edge first.
The tax rate can be 0% while the subsidy cost is thousands.
A raise does not make all income taxed at the higher ordinary bracket. Real cliffs are less common and more dangerous.
This map is a 2026 edition. Recheck before acting in any later tax year.
Primary sources used
- CMS: 2026 Medicare Parts A & B Premiums and Deductibles; Part D IRMAA
- IRS Rev. Proc. 2025-32: 2026 tax inflation adjustments
- IRS Notice 2025-67: 2026 retirement-plan and IRA limits
- IRS Rev. Proc. 2025-25: 2026 premium tax credit applicable percentages
- IRS Premium Tax Credit overview and APTC reconciliation rules
- HHS/ASPE 2026 poverty guidelines
- SSA: 2026 retirement earnings test and SSA retirement benefits publication
- Federal Student Aid: 2027-28 SAI and Pell Grant Eligibility Guide
- IRS: enhanced senior deduction, NIIT, Additional Medicare Tax, and education credits