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How Student Loan Repayment Actually Works
Subsidized versus unsubsidized, the grace period, capitalization, and why a smaller monthly payment can cost tens of thousands more. Worked with real numbers.
By the Euphoria team · 2026-07-27 · 7 min read
Key points
- Interest on a $30,000 loan at 6.52 percent runs $163 a month, and every repayment question reduces to whether the payment beats that figure.
- Stretching the same loan from ten years to thirty cuts the payment by about $151 a month and raises total interest from $10,914 to $38,405.
- Capitalization adds unpaid interest to principal, so $978 of grace-period interest ends up costing $1,334 across a ten-year term.
- Federal loans carry income-driven plans and statutory deferment rights that private student loans do not, and that gap matters more than the rate.
One number decides everything else
Take a $30,000 federal student loan at 6.52 percent, the rate set for undergraduate loans first disbursed in the 2026-27 year. Multiply the balance by the rate and divide by twelve, and you get $163. That is how much interest the loan generates in a month.
Almost every question about student loan repayment is really a question about whether your payment is above or below $163. Pay more, and the balance falls. Pay less, and the balance grows while you are paying it. The plans, the forms, the grace periods, and the vocabulary all sit on top of that one comparison.
Here is how the machinery around it works.
Your rate came from one Treasury auction
Federal student loan rates are not set by a bank looking at your credit, and they are not set by the Department of Education choosing a number. They come from a formula written into the Higher Education Act.
Each year the rate equals the high yield on 10-year Treasury notes at the last auction before June 1, plus a fixed add-on that depends on the loan type. For 2026-27 that auction landed on May 12, 2026 with a high yield of 4.468 percent, and the add-ons produced these rates:
- 6.52% undergraduate subsidized and unsubsidized loans, 2026-27
- 8.07% graduate and professional unsubsidized loans
- 9.07% PLUS loans for parents and graduate students
Two consequences follow. First, the rate is fixed for the life of that loan, so a borrower with four years of loans usually has four different rates sitting in one account. Second, the year you borrow matters more than anything about you: a student who borrowed in a low-yield year and a student who borrowed in a high-yield year carry different rates for decades on identical paperwork.
What the word subsidized actually buys
A subsidized loan and an unsubsidized loan are both federal loans at the same rate for undergraduates. The difference is who pays the interest during the periods when you are not making payments.
On a subsidized loan, the government covers the interest while you are enrolled at least half time, during your grace period, and during certain deferments. Nothing accrues to you in those windows. On an unsubsidized loan, interest accrues from the day the money is disbursed, including every semester you are still in class.
Run that over a degree. A student who borrows unsubsidized money in the first year carries interest on it for four years of school plus a grace period before the first bill arrives. A student who borrows the same amount subsidized starts repayment owing exactly what was borrowed. Same headline rate, materially different loan. Subsidized loans are awarded based on financial need, which is why the FAFSA determines the mix you are offered rather than you choosing it.
The grace period, and the moment interest becomes principal
Federal Direct loans generally give you six months after you leave school before payments start. The name misleads people, because on unsubsidized loans the meter is running the whole time. On our $30,000 example, six months of accrual at $163 a month adds $978. You did nothing wrong and you owe another $978.
Then comes the step most borrowers do not see happening, and it is the one that quietly changes the arithmetic.
Capitalization is the moment unpaid accrued interest is added to your principal balance. After it happens, the interest that had been sitting in a separate bucket becomes part of the amount your interest rate is applied to. You start paying interest on interest.
Follow the example through. The $978 capitalizes at the end of the grace period, so the principal becomes $30,978. Monthly interest rises from $163.00 to $168.31. On a ten-year standard plan the payment rises from $340.95 to $352.06, and the total repaid rises from $40,914 to $42,248. That is $1,334 more in total for $978 of accrued interest. The extra $356 is the interest charged on the capitalized interest.
Capitalization is triggered by specific events rather than happening continuously: the end of a grace period on unsubsidized loans, the end of a period of forbearance, consolidation, and leaving certain repayment plans. The events are knowable in advance, which is the only reason this fact is useful.
The standard plan, and what a longer term really costs
The default is the standard ten-year plan: a fixed payment sized so the loan is fully repaid in 120 months. On $30,000 at 6.52 percent that is $340.95 a month, and $40,914 over the full term, of which $10,914 is interest.
Stretch the same loan over a longer term and the monthly number gets friendlier while the total gets worse.
- Ten years: $340.95 a month, $40,914 total.
- Twenty years: $224.03 a month, $53,766 total.
- Thirty years: $190.02 a month, $68,405 total.
| Period | Total amount repaid |
|---|---|
| 10-year term | $40,914 |
| 20-year term | $53,766 |
| 30-year term | $68,405 |
Same balance, same rate. Only the term changes. These are standard amortization calculations, so the arithmetic is the source.
Moving from ten years to thirty cuts the monthly payment by about $151, which is real money in a real budget. It also more than triples the interest, from $10,914 to $38,405. The reason is mechanical rather than mysterious: interest accrues on whatever principal is still outstanding, and a smaller payment leaves more principal outstanding for longer. You are renting the money for twenty additional years.
A lower monthly payment is not a discount. It is the same debt, charged for more time.
Income-driven plans and the tradeoff they make
An income-driven plan sizes your payment from your income rather than from your balance. That is the whole idea, and it cuts both ways.
The plans currently described on studentaid.gov work like this. The Repayment Assistance Plan, or RAP, charges 1 to 10 percent of adjusted gross income divided by twelve, reduces that by $50 for each dependent, never falls below $10 a month, and discharges any remaining balance after 30 years. Income-Based Repayment charges 15 percent of discretionary income, or 10 percent for borrowers whose first loan came on or after July 1, 2014, never more than the standard ten-year payment, over 25 years or 20 for those newer borrowers. Pay As You Earn charges 10 percent of discretionary income over 20 years, and Income-Contingent Repayment charges the lesser of 20 percent of discretionary income or a payment based on a 12-year fixed schedule. Both of those last two are scheduled to end no later than July 1, 2028. For loans first disbursed on or after July 1, 2026, RAP is the only income-driven option.
Now the arithmetic these plans run into. Suppose an income-driven formula produces a $120 payment on our $30,000 balance, below the $163 of monthly interest. After ten years of paying every month on time, the borrower has paid $14,400 and owes about $37,249.
| Period | Balance still owed |
|---|---|
| $120 a month | $37,249 |
| $163 a month | $30,000 |
| $200 a month | $23,762 |
$163 is exactly one month of interest on $30,000 at 6.52 percent. Below that line the balance grows even though every payment was made. The arithmetic is monthly accrual on the outstanding balance.
That outcome is called negative amortization, and it is not a penalty for doing something wrong. It is what happens when a payment is set by income while interest is set by balance. Whether the borrower comes out ahead depends entirely on the discharge at the end of the term and on whether the plan subsidizes the uncovered interest, which RAP does and the older plans largely do not. Those are the two variables to compare, and they matter far more than the monthly number.
Federal and private loans are not the same product
Everything above describes federal loans. A private student loan is a bank product governed by its contract.
Private loans can carry variable rates that move over the life of the loan. They usually require a credit check and often a co-signer, which puts another person's credit on the line. Most importantly, they carry none of the federal protections: no income-driven plans, no statutory deferment rights, no public service discharge, and no guarantee of a hardship option beyond what the lender chooses to offer.
That is why the federal or private distinction is the first thing to establish about any loan, before the rate. Two loans at the same interest rate are not equivalent if only one of them has a legal floor under what happens when your income drops.
Why this matters for you
Nothing here tells you which plan fits a particular life, and it should not. What it gives you is the ability to check any repayment claim yourself: multiply balance by rate, divide by twelve, and compare the result to the proposed payment. If the payment is smaller, you now know the balance will grow and you know to look for whether the interest is subsidized and when the term ends.
Euphoria turns that comparison into practice, with loan scenarios you can run at different rates, terms, and incomes, so the arithmetic is already familiar by the time a real promissory note is in front of you.