Student Loans, RAP vs. IBR
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Dear Prosperics Users,
If you carry federal student loans, 2026 is the year the repayment map got redrawn. The SAVE plan is gone, the Repayment Assistance Plan (RAP) is here, and Income-Based Repayment (IBR) survives as the main legacy income-driven option. The choice between them is not obvious — and picking wrong can cost you thousands of dollars or years of extra payments.
We built our Federal Student Loan Calculator specifically to compare these plans side by side with your actual numbers. In this article we explain how each plan computes your payment, then run three borrower profiles through the math so you can see the crossover points for yourself.
How RAP calculates your payment
RAP breaks from the "discretionary income" formula that defined the older income-driven plans. Instead of subtracting a poverty-line multiple from your income first, RAP applies a percentage directly to your adjusted gross income (AGI), on a sliding scale: lower AGI bands pay a smaller percentage, higher bands pay more, up to 10% of AGI. Three features matter most in practice:
A minimum payment of $10 per month. Unlike SAVE, nobody pays $0 on RAP. That sounds trivial, but it changes forgiveness math for very-low-income borrowers, because every month now requires an actual payment.
Unpaid interest is waived. If your calculated payment doesn't cover the month's interest, the difference doesn't capitalize — your balance doesn't grow while you're paying as agreed. This is RAP's most valuable feature for high-balance, moderate-income borrowers.
A small principal credit. In months where your payment covers interest but little principal, RAP tops up the principal reduction, so balances slowly decline instead of treading water.
Forgiveness on RAP arrives after 30 years of qualifying payments — longer than the 20- or 25-year horizons of the legacy plans. That single number is why RAP is not automatically the right answer.
How IBR calculates your payment
IBR is the survivor of the legacy income-driven family. It charges 10% of discretionary income for newer borrowers (15% for older ones), where discretionary income is your AGI minus 150% of the federal poverty guideline for your family size. Forgiveness comes at 20 years for newer borrowers, 25 for older ones. IBR also has a feature RAP lacks: a payment cap at the 10-year standard amount, which protects high earners whose income spikes late in repayment.
Three borrower profiles, one honest comparison
Profile 1: New graduate, $38,000 AGI, $31,000 balance, single
On IBR, this borrower subtracts roughly $23,000 (150% of the poverty line for a single filer) from AGI, leaving about $15,000 of discretionary income. Ten percent of that is $1,500 a year, or about $125 a month. On RAP, the payment comes straight off AGI at the applicable band — a materially higher monthly bill for the same income.
But look at the balance. At $31,000 with a moderate payment, this borrower plausibly pays the loan off before either forgiveness horizon matters. When forgiveness is unlikely to trigger, the comparison collapses to a simpler question: which plan clears the debt with less total interest? Run both in the calculator — for many borrowers in this bracket, the plan with the higher monthly payment wins on total cost.
Profile 2: Social worker, $52,000 AGI, $95,000 of graduate debt, pursuing PSLF
Public Service Loan Forgiveness changes everything, because PSLF forgives after 120 qualifying payments regardless of which qualifying plan you're on. Here the strategy is to minimize the total paid over exactly 10 years — you want the lowest monthly payment you can legally make. Whether RAP or IBR delivers a lower payment depends on family size (IBR's poverty-line deduction scales with dependents; RAP uses AGI bands). For a single filer at $52,000, IBR's discretionary-income discount usually keeps its payment lower. For a family of four at the same income, the gap widens further in IBR's favor.
Profile 3: Physician assistant, $110,000 AGI, $180,000 balance
High balance, high income — this is where RAP's interest waiver earns its keep. On IBR, a payment of roughly $725 a month may not cover the interest on $180,000, and while IBR doesn't capitalize that unpaid interest in most cases, the balance still doesn't shrink. On RAP the payment is higher, but the waiver plus principal credit means the balance actually declines every single month. If this borrower expects income growth (and most do), RAP's structure often produces a lower lifetime cost even before considering the tax bomb below.
Don't forget the tax bomb
Forgiveness under RAP or IBR (outside PSLF) is potentially taxable as income in the year it happens. A borrower forgiven $120,000 in 2046 could face a five-figure federal tax bill in a single year. Our calculator projects this explicitly — it's the number most online comparisons quietly omit, and it can flip the ranking between two plans that look close on monthly payment alone.
The decision framework
Pursuing PSLF: Whichever qualifying plan gives the lowest payment — often IBR
Balance smaller than your annual income: Compare total interest to payoff; forgiveness rarely matters
Balance 1.5× your income or more: RAP's interest waiver vs. IBR's shorter forgiveness — model both
Large family, moderate income: IBR — the poverty-line deduction works hard for you
These are starting points, not answers. The honest answer depends on your AGI trajectory, family size, and how each plan's forgiveness clock interacts with your timeline — which is exactly what the calculator models, including SAVE transition paths and filing-status optimization for married borrowers.
Educational content only — not financial advice. Figures current as of publication; always confirm plan terms at studentaid.gov.
Prosperics Editorial Board