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.