Interest is one of the biggest challenges borrowers face when repaying student loans. Because of daily accrual and compounding rules, balances can grow faster than many people expect. The key to paying off your debt efficiently is understanding how interest works — and spotting when your servicer may not be applying payments correctly.
In this guide, we’ll break down how student loan interest accrues, when it compounds, and strategies you can use to minimize interest costs.
Are Student Loans Compound Interest or Simple Interest?
Student loans mostly use simple interest, not true compound interest. Interest accrues daily on the principal balance, and it only becomes compound interest when unpaid interest is capitalized and added to your loan balance. Once that happens, you’re charged interest on a larger balance, which now includes the old interest.
This is why some borrowers feel like their balances never go down, even when they’ve been making payments.
Does Student Loan Interest Compound Daily?
A common misconception is that student loans compound daily. In reality:
- Interest accrues daily — your balance grows a little each day based on your loan amount and interest rate.
- Interest compounds only when it capitalizes — capitalization is event-driven, not routine. It happens during specific triggers such as leaving forbearance or deferment, switching repayment plans, consolidating, or missing income-driven repayment recertification deadlines.
So while interest builds daily, it does not compound daily. Compounding only happens when unpaid interest is capitalized.
How Often Do Student Loans Compound?
Most federal and private student loans accrue interest daily but compound only at capitalization events. These are tied to borrower actions or loan status changes, not a fixed monthly schedule.
For example:
- A $10,000 loan at 5% accrues about $1.37 in interest per day.
- After a period such as the end of a forbearance, deferment, grace period, or failure to recertify income on an income-driven repayment (IDR) plan, unpaid accrued interest is capitalized—added to your balance.
- From that point, you’ll start paying interest not just on the original $10,000 but also on the interest that was added.
This cycle is what makes compound interest so costly over time.
What Is Accrued Interest vs. Capitalized Interest?
These two terms often confuse borrowers:
- Accrued Interest: The amount of interest that has built up on your loan but hasn’t yet been added to your principal. You’ll see this listed on your billing statements each month.
- Capitalized Interest: This happens when any unpaid interest is added to your loan’s principal balance. From that point forward, you’re paying interest on a larger amount.
Capitalization can happen at specific times, like when you:
- Leave forbearance or deferment.
- Fail to recertify income for an IDR plan.
- Consolidate your loans.
If you’re surprised to find your balance growing despite making payments, our article Why I still owe on my student loans explores in detail why this happens and what options you may have.
Processing Payments: Interest, Fees, and Principal
When you make a student loan payment, your servicer doesn’t apply all of it straight to your balance. Instead, payments are typically applied in this order:
- Fees – Late fees or other charges get covered first.
- Interest – Any unpaid, accrued interest is paid next.
- Principal – Whatever remains is applied to your loan balance.
This order matters because lenders benefit from collecting interest first. It also means that if you want extra payments to count toward your principal (to save on future interest), you need to explicitly instruct your servicer to apply them that way. Learn more about payment allocation.
Some lenders, like Sallie Mae, have even applied overpayments to future bills instead of knocking down principal — a practice that frustrated many borrowers and even sparked lawsuits. To avoid this problem, always confirm in writing how you want extra payments handled.
Student Loan Interest Rates and Why They Change
While this page focuses on how interest accrues and compounds, it’s also important to understand why your loan’s interest rate might change.
- Congress sets federal student loan rates each year, and once you borrow, that rate is locked in for the life of your loan.
- Private loans can be either fixed or variable. Variable loans are tied to market indexes and may reset monthly, quarterly, or annually.
If your rate goes up, your monthly payment will rise too.
How Student Loan Interest Adds Up Over Time
Let’s look at a simplified example:
- Loan balance: $10,000
- Interest rate: 5%
- Daily interest: $1.37
If you don’t make any payments, after one month you’ll owe about $41 in accrued interest. Once that interest is capitalized, your balance grows to $10,041.
From that point on, interest is calculated on the new balance — meaning the longer you go without tackling accrued interest, the more expensive your loan becomes.
If you want to check the most up-to-date federal student loan interest rates for the 2025-2026 academic year, you can find them here.
To calculate the interest online – There are many interest online calculators. This calculator makes the process simple and is ideal for estimating interest generated in a day, a month, a year, or over the life of the loan.
How to Reduce the Cost of Student Loan Interest
The best way to fight interest is to limit how much accrues and avoid capitalization whenever possible. Some strategies include:
- Pay more than the minimum: Extra payments directed to your principal cut down your balance and future interest charges.
- Avoid capitalization triggers: Stay current on recertification deadlines and avoid unnecessary forbearances.
- Target accrued interest: Ask your servicer to apply extra payments directly to accrued interest or principal.
- Explore lower rates: Federal borrowers may benefit from programs like the SAVE plan’s interest subsidy. Private borrowers might consider refinancing if they qualify for a lower rate.
Note: Some federal borrowers previously benefited from programs like the SAVE plan’s interest subsidy. However, the SAVE plan’s subsidy is currently paused due to court injunctions, and interest accrual is scheduled to resume on August 1, 2025.
The sooner you reduce your balance, the less opportunity interest has to snowball.
Further Read: Explore ways to lower student loan interest.
Does student loan interest accrue during school?
Many student loans come with special rules for students who are still in school. With the notable exception of a federal subsidized loan, student loans do accrue interest during school.
FAQs About Student Loan Interest
Student loans typically accrue interest daily using simple interest, not true compound interest. Interest accrues daily on the principal balance, and compound interest occurs only when unpaid interest is capitalized—added to the principal balance—causing interest to be charged on that new higher balance.
No. They accrue daily but do not compound daily. Instead, interest compounds when unpaid interest is capitalized, which usually happens at specific times, such as ending deferment or forbearance, consolidating loans, switching repayment plans, or missing income-driven repayment recertification.
It accrues daily but only compounds (capitalizes) periodically, usually monthly or during specific capitalization events.
Accrued interest is unpaid interest that builds daily. Capitalized interest is when that unpaid interest gets added to your principal balance.
About the Author
Pedro Gomez is the new Student Loan Sherpa and a Certified Financial Planner™ with over a decade of experience helping clients navigate complex financial decisions. He is the founder of Global Financial Plan, where he writes about international living, geoarbitrage, and strategies for retiring young, and also leads Brickell Financial Group, a registered investment advisory firm focused on accelerating financial freedom.
Pedro is the architect behind the “12 Levels of Financial Freedom” framework and blends student loan strategy with long-term planning, tax efficiency, and investing. His work is especially geared toward upwardly mobile professionals, entrepreneurs, and those looking to design a life beyond the default path.
Pedro is available for strategy sessions and press inquiries.
