Income-Driven Repayment: Why Your Balance Grows

By Alamzeb Khan · Updated August 2026 · 6 min read · Income-Driven Repayment Calculator →

The thing nobody warns you about

You earn $48,000. You owe $60,000 at 6.5%. On the standard ten-year plan the payment would be $681 a month, which you cannot manage.

An income-driven plan puts it at $200.50. Enormous relief.

Then, two years in, you check the balance and it is higher than when you started.

From the income-driven repayment calculator, on a plan taking 10% of discretionary income over twenty years:

You pay for twenty years and owe twice what you started with.

Why it happens

Interest is charged on the balance every month - here, about $325.

Your payment is $200.50. The other $124.50 does not disappear; it is added to what you owe. Next month interest is charged on the slightly larger balance, and so on for 240 months.

That is called negative amortisation, and it is not a mistake or a penalty. It is the arithmetic of paying less than the interest, and income-driven plans are explicitly designed to allow it.

Why it is not the disaster it looks like

The plan forgives whatever is left at the end. The $121,057 is never something you have to find.

So the honest way to read it: you pay $48,120 over twenty years and the loan ends. The balance in between is a number on a statement, not a bill.

That said, three things are worth knowing:

If you leave the plan, the balance is real. Refinance privately, or move to a standard plan, and you take the grown balance with you.

It feels terrible. Watching a debt grow for twenty years while paying every month is genuinely hard, and people quit plans over it. Knowing it is coming makes it survivable.

The forgiven amount may be taxable. Whether it is has changed more than once depending on the programme and the year. It is a large enough number that it is worth checking the current position at studentaid.gov rather than assuming either way.

How the payment is worked out

It is not a percentage of your salary, which is what most people assume.

1. Start with your income - $48,000.
2. Subtract a multiple of the poverty guideline for your household. At 150% for a single person, that is $23,940.
3. What is left is discretionary income: $24,060.
4. Take the plan’s percentage of that, divided by twelve. At 10%: $200.50.

Two consequences fall out of this:

A bigger household means a lower payment, because the poverty line subtracted is larger.

Below the line, the payment can be zero - and zero payments still count toward forgiveness.

The plans are genuinely different

Same borrower, four plans:

The 20% plan uses a smaller poverty subtraction, so more of your income counts as discretionary. The payment is high enough to beat the interest, so the balance actually falls and the loan clears in fourteen and a half years.

It costs $44,796 more than the cheapest plan. It also ends fully paid, with nothing forgiven and no question about tax.

Which is better depends entirely on your circumstances and your expectations about future income. There is no universally right answer here, which is why seeing all of them together matters.

Before you choose

1. Work out one month’s interest - balance times rate divided by twelve. If your payment is below that, your balance will grow.
2. Decide whether you can live with that for the full term.
3. Compare the plans on total paid, not on the monthly payment.
4. Recertify your income every year. Missing it can push you off the plan.
5. Check the tax position before counting on forgiveness.

Run your own numbers through the income-driven repayment calculator - it shows every plan side by side and says plainly when a payment will not cover the interest.

Common questions about income-driven repayment