The simple version

Under the revised federal income-driven repayment rules, new borrowers with undergraduate loans will have their monthly payment capped at 5% of discretionary income, down from the 10% cap that applied under older plans like REPAYE and IBR. On a $40,000 income, that difference is roughly $100 less per month right out of the gate, before interest even enters the picture.

The overhaul also changes how discretionary income is defined, which lowers the base the percentage is applied to. That means the actual payment reduction can be larger than the percentage cut suggests. For borrowers already in repayment, the transition rules matter as much as the new caps. If you have federal student loans, your monthly bill, your forgiveness timeline, and the total interest you pay over the life of the loan can all shift depending on which plan you are on and when you enrolled.

The numbers

• New income-driven repayment cap for undergraduate loans: 5% of discretionary income, down from 10% under REPAYE and standard IBR (Federal Student Aid, studentaid.gov).
• Discretionary income is now defined as income above 225% of the federal poverty line, up from 150% under older plans, which shrinks the base the percentage applies to (Federal Student Aid, studentaid.gov).
• Borrowers with original loan balances of $12,000 or less can qualify for forgiveness after 10 years of payments under the revised rules, down from 20 to 25 years under older income-driven plans (Federal Student Aid, studentaid.gov).
• Total federal student loan debt in the United States stood at approximately $1.6 trillion as of early 2026, held by roughly 43 million borrowers (U.S. Department of Education, ed.gov).
• Public Service Loan Forgiveness remains at 10 years of qualifying payments and is separate from the income-driven repayment forgiveness timeline changes (Federal Student Aid, studentaid.gov).
• Borrowers with a mix of undergraduate and graduate loans have a blended payment cap between 5% and 10% of discretionary income, weighted by loan balance (Federal Student Aid, studentaid.gov).

How income-driven repayment actually calculates your bill

Income-driven repayment does not look at your loan balance to set your monthly payment. It looks at your income and family size. The formula starts with your adjusted gross income, subtracts a protected amount tied to the federal poverty line, and then takes a percentage of what is left. That remainder is your discretionary income, and your monthly payment is a fixed share of it.

Under the older REPAYE plan, the protected floor was 150% of the federal poverty line. Under the revised rules, it rises to 225%. For a single borrower earning $40,000, the poverty line for 2025 is roughly $15,060 (Department of Health and Human Services, hhs.gov). At 150%, the protected amount is $22,590, leaving $17,410 as discretionary income, and 10% of that is $1,741 per year, or about $145 per month. At 225%, the protected amount rises to $33,885, leaving only $6,115 as discretionary income, and 5% of that is $306 per year, or roughly $26 per month. The payment on the same income can look dramatically different depending on which formula applies.

The forgiveness clock is also part of the calculation. Under older plans, most borrowers waited 20 to 25 years for any remaining balance to be forgiven. Under the revised rules, the timeline shortens for borrowers with smaller original balances, reaching 10 years for those who borrowed $12,000 or less. Each additional $1,000 borrowed adds one year to the forgiveness clock, up to a maximum of 20 years for undergraduate debt.

What the lower payment actually does to total interest paid is not obvious. A lower monthly payment means more months in repayment for larger balances, which means more time for interest to compound. Borrowers with high balances and low incomes can still see their balance grow even while making on-time payments, a dynamic called negative amortization. The revised rules include an interest subsidy for borrowers whose payments do not cover their monthly interest, which limits runaway balance growth, but it does not eliminate the tradeoff between lower payments and longer repayment periods.

The Real Cost lens on a $35,000 undergraduate balance at $40,000 income

Here is what the payment difference looks like on a specific borrower: $35,000 in undergraduate loans, a 6.5% federal interest rate, single filer, $40,000 adjusted gross income. The comparison is the old REPAYE plan versus the revised 5% cap.

• Old REPAYE monthly payment (10% cap, 150% poverty floor): approximately $145 per month.
• Revised plan monthly payment (5% cap, 225% poverty floor): approximately $26 per month.
• Monthly difference: $119 less under the revised plan.
• Over 20 years, at $119 per month reinvested at a 7% average annual return instead of paid toward the loan, the opportunity value of that freed cash is approximately $74,000. The tradeoff: a longer repayment window means more total interest paid unless the balance is forgiven.

The lower payment frees cash every month, but it does not eliminate the debt. For a $35,000 balance at 6.5% where payments barely cover interest, the forgiveness at year 20 could mean a large cancellation of principal. Under current tax law, forgiven loan balances on income-driven plans may be treated as taxable income in the year of forgiveness. That tax bill, sometimes called the forgiveness tax bomb, is a real cost that belongs in any honest comparison of repayment paths.

What this means

For borrowers just entering repayment, the revised rules represent a real reduction in monthly cash pressure, particularly for those with lower incomes and undergraduate-only debt. The 225% poverty floor change alone can move a payment from triple digits to double digits on a moderate income, which changes what else a borrower can do with their monthly budget.

For borrowers already enrolled in older income-driven plans, the picture is more complicated. Transitions between plans can reset forgiveness clocks in some cases and not in others. The interest subsidy rules, the forgiveness timeline tables, and the tax treatment of forgiven balances are each their own layer of the decision. The overhaul changes the structure of the program, but it does not simplify the decision of which plan fits any individual borrower's situation.

What this is NOT

This is not a prediction of whether these repayment rules will survive pending legal challenges or future legislative changes. This is not advice on whether to switch repayment plans, consolidate loans, or pursue Public Service Loan Forgiveness. This is not a calculation of what any individual borrower will owe, since actual payments depend on income, family size, loan type, and enrollment date. This is not guidance on the tax consequences of loan forgiveness for any specific borrower. This is not a recommendation about any loan servicer, financial product, or repayment strategy.

Sources

• Federal Student Aid, income-driven repayment plan information: https://studentaid.gov
• U.S. Department of Education, student loan data and policy: https://ed.gov
• U.S. Department of the Treasury: https://treasury.gov