Roth Conversion ACA Subsidy Cliff 2027 Calculator
If you're under 65 buying ACA Marketplace coverage, a Roth conversion can blow up your premium tax credit (PTC). With the enhanced PTC subsidies expiring after 2025, 2027 returns to the original 400% FPL cliff for many filers. This tool finds the conversion size that preserves your subsidy.
What Is the ACA Subsidy Cliff?
The Affordable Care Act's premium tax credit (PTC) historically used a hard 400% Federal Poverty Level cliff — earn $1 over and you lose 100% of the subsidy. The American Rescue Plan (2021) and Inflation Reduction Act (2022) temporarily replaced the cliff with a sliding scale capped at 8.5% of MAGI, extended through plan year 2025. Without congressional renewal, 2026 and 2027 ACA coverage returns to the original 400% FPL cliff for most filers — making the ACA subsidy cliff one of the most painful tax traps in early retirement. Source: IRC Section 36B and KFF 2026 ACA subsidy projection. Last updated: May 2026.
2027 Federal Poverty Level (Estimated) — 48 States + DC
| Household Size | 100% FPL | 400% FPL (Cliff) |
|---|---|---|
| 1 | ~$16,150 | ~$64,600 |
| 2 | ~$21,850 | ~$87,400 |
| 3 | ~$27,550 | ~$110,200 |
| 4 | ~$33,250 | ~$133,000 |
| 5 | ~$38,950 | ~$155,800 |
Why Roth Conversions Trigger the Cliff
The PTC is calculated based on Modified Adjusted Gross Income (MAGI), which includes the gross amount of any Roth conversion. So a $30,000 conversion adds $30,000 to MAGI. For a 60-year-old couple with $50,000 of regular income near the FPL cliff, that conversion pushes them above 400% FPL and triggers loss of the entire premium tax credit — often $10,000+ per year. The effective marginal tax rate of a cliff-crossing conversion can exceed 50% when you add federal income tax, state tax, and lost subsidy.
Strategic Conversion Sizing for ACA Filers
Three rules for early retirees on ACA coverage: (1) Calculate your 400% FPL ceiling using the projected 2027 figures above and your household size. (2) Subtract your other expected income (capital gains, dividends, IRA distributions) — that's your conversion headroom. (3) Convert only up to 90% of headroom to leave buffer for year-end dividend surprises. If your conversion need is larger than headroom, wait until age 65 (Medicare coverage starts, ACA cliff irrelevant). Or split conversions across multiple years to stay below the cliff each year.
Frequently Asked Questions
What is the ACA subsidy cliff in 2027?
Without renewal of the American Rescue Plan / Inflation Reduction Act PTC enhancements, 2026 and 2027 ACA coverage reverts to a hard 400% Federal Poverty Level cliff. Earn $1 over and you lose 100% of the premium tax credit. Source: IRC Section 36B.
How does a Roth conversion affect ACA subsidies?
Roth conversion amounts add directly to your MAGI. If the conversion pushes MAGI over 400% FPL, you lose the entire premium tax credit — often $5,000–$15,000 per year for a couple. This makes Roth conversions in early retirement (pre-65) extremely tax-sensitive.
What is the 2027 400% FPL threshold for ACA?
Estimated: ~$64,600 for a 1-person household, ~$87,400 for 2 people, ~$110,200 for 3, ~$133,000 for 4 (48 states + DC; Alaska and Hawaii higher). 2027 FPL is finalized in January 2027 by HHS.
What is the effective marginal tax rate at the ACA cliff?
Often 50%+ when you combine federal income tax (12–22%), state tax (5–10%), and the lost subsidy. For a $30,000 conversion that crosses the cliff and loses a $10,000 subsidy, the effective rate is roughly: ($30,000 × 12% federal + $10,000 lost subsidy) / $30,000 = ~45%.
Should I wait until age 65 to do Roth conversions?
Often yes if you're on ACA coverage. Once Medicare kicks in at 65, the ACA cliff disappears (though IRMAA cliffs replace it 2 years later). Many early retirees do small below-cliff conversions until 65, then larger conversions in their Medicare gap years before RMDs at 73 or 75.