How Student Loan Interest Actually Works

Author
Grace Lemire
Grace Lemire
author

Grace Lemire is a freelance writer and editor with over five years of experience in the personal finance industry. She has been featured on a variety of publications, including NPR, CNN, FinanceBuzz, Dollar Geek, Pangea, and True Finance. Her work focuses on the intersection of personal finance and technology. In 2023, Grace was nominated for the Best Personal Finance Advice award in Debt.com’s FinTok Awards.

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Edited by
Daniel Kahn
Daniel Kahn
editor
Daniel is the co-founder and COO at Sparrow. Daniel is responsible for the day-to-day operations of a company, working closely with other members of the executive team to develop and implement strategies to support the growth and success of the company.
Daniel was a 2023 Forbes 30 Under 30 lister in the Education category.  Daniel was born and raised in Raleigh, North Carolina and graduated from Duke University in 2020.
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Reviewed by
Camden Ford
Camden Ford
reviewer

Camden leads Sparrow’s business operations – everything from product management to business analytics. After graduating Cum Laude from Duke University where he studied Civil Engineering, Camden worked as a Consultant for A.T. Kearney where he worked in their Strategic Operations practice. With a strong background in analytics, Camden strives to deliver data-driven conclusions and insights.

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Updated
January 24, 2024

You make a loan payment. The total debt goes down.

Then you come back the next day. The loan amount is back up to where it was before your payment.

Having some deja vu?

This is because of interest. Let’s break down what interest is, how it works, and why your total loan balance may be going up so quickly.

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What Is Interest?

Interest is essentially the amount you pay a lender to use their money to pay for college. When a lender decides to give you money, they make a profit off of the interest paid over time on top of the original loan amount.

Most lenders understand that students will not be able to make loan payments while in school and often don’t require payments until a few months after you leave school. However, this does not mean that interest isn’t accruing on the overall debt amount. This means that the amount you owe can go up, and fairly rapidly if you don’t pay close attention to it.

How Does Interest Work?

It’s one thing to understand the concept of interest, but it’s another thing to really understand how it’s calculated. Let’s break it down.

(As a refresher before we get started, principal is the initial amount you agreed to pay back. Interest is the price you pay to borrow that money. For example, if you borrowed $30,000 to pay for college, and your loan balance is currently $40,000, $30,000 of that is principal, and $10,000 of that is interest.)

When you make a required monthly loan payment, you’re making a payment on the interest before any money goes toward reducing your principal. Whatever is left over after paying the interest is then put towards the principal balance. Over the life of your loan, the interest paid will go down each month, which subsequently allows you to put more towards your principal.

To break this down even further, we’ll use an example with some simple numbers.

Say you borrowed $100 from a lender some years ago, and your balance is now $120. You owe $100 in principal and $20 in interest. If you make a $10 payment towards your debt, you will be paying $10 towards the interest on your debt, bringing your overall total debt down to $110. However, the amount you just paid hasn’t chipped away at actually paying back what you initially borrowed. You simply paid part of what the lender is charging you to borrow that money.

How Does Interest Compound?

Interest is typically compounded daily. So what exactly does that mean?

The annual interest rate is divided by 365 (the days in the year) to get your daily interest rate. That is how much your interest will compound daily. The kicker is that if you aren’t making loan payments, the interest is compounding on a larger and larger amount.

This is what that can look like: (Get ready for some *quick maths.*)

Let’s say you borrowed $10,000 from a lender with a 5% interest rate.

Your daily interest rate would be roughly 0.014% (5% ÷ 365).

On day 1, your total loan debt would be $10,000.

On day 2, it would be $10,001.40.

For day 3, your interest would be calculated based on this new amount of $10,001.40, meaning…

Day 4, your total loan debt would be $10,0002.80.

At the end of a year, you would have accumulated a decent chunk in interest.

This compounding takes place when you are in school and beyond, so, you can imagine how this number can increase so rapidly if you aren’t making payments while in school.

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How Much Interest Will I Pay?

This will vary from person to person depending on your total loan amount and the interest rate.

The average student loan accrues $26,000 in interest over the course of 20 years. This interest ends up being around 67.1% of the average borrower’s total cost of repayment. This means that over half the amount paid over time is strictly from interest.

For a specific calculation based on your individual loan information, we recommend using Sallie Mae’s Accrued Interest Calculator.

What is Considered a High Interest Rate?

This might lead you to ask about what is considered to be a good interest rate. The reality is, interest rates vary greatly by lender and type of loan. So, it’s hard to say what is good and what isn’t.

Generally speaking, anything at or above 10% is considered a very high interest rate for student loans. Interest rates at 7% and below is a much better place to be.

Between 2006 and 2021, the average federal student loan interest rates were:

4.66% for undergraduates

6.22% for graduate students

7.27% for parents and grads who take out PLUS loans

In May 2018, the average private loan interest rates were:

6.17% for borrowers with 5-year variable-rate loans with a cosigner and beginning repayment immediately

7.64% for borrowers with 10-year fixed-rate loans with a cosigner beginning repayment immediately

How Can I Lower the Amount of Interest that Accrues?

The best way to prevent your total debt amount from rising so rapidly is to make at least the minimum monthly payments. On top of that, you can also save on interest by making biweekly and surplus payments.

If possible, you should always aim to pay off the interest that has accumulated to keep the loan at its initial amount.

Student loan rates from our partners
lender Ascent logo
Ascent
Minimum credit score
Varies
Fixed APR
Fixed APR

Ascent’s undergraduate and graduate student loans are funded by Bank of Lake Mills, or DR Bank, each Member FDIC. Loan products may not be available in certain jurisdictions. Certain restrictions, limitations; and terms and conditions may apply. For Ascent Terms and Conditions please visit: www.AscentFunding.com/Ts&Cs. Rates are effective as of 11/1/2024 and reflect an automatic payment discount of either 0.25% (for credit-based loans) OR 1.00% (for undergraduate outcomes-based loans). Automatic Payment Discount is available if the borrower is enrolled in automatic payments from their personal checking account and the amount is successfully withdrawn from the authorized bank account each month. For Ascent rates and repayment examples please visit: AscentFunding.com/Rates. 1% Cash Back Graduation Reward subject to terms and conditions. Cosigned Credit-Based Loan student must meet certain minimum credit criteria. The minimum score required is subject to change and may depend on the credit score of your cosigner. Lowest rates require full
principal and interest payments, the shortest loan term, a cosigner, and are only available for our most creditworthy applicants and cosigners with the highest average credit scores. Actual APR offered may be higher or lower than the repayment examples above, based on the amount of time you spend in school and any grace period you have before repayment begins.

3.69 - 15.04%
Variable APR
Variable APR

Ascent’s undergraduate and graduate student loans are funded by Bank of Lake Mills, or DR Bank, each Member FDIC. Loan products may not be available in certain jurisdictions. Certain restrictions, limitations; and terms and conditions may apply. For Ascent Terms and Conditions please visit: www.AscentFunding.com/Ts&Cs. Rates are effective as of 11/1/2024 and reflect an automatic payment discount of either 0.25% (for credit-based loans) OR 1.00% (for undergraduate outcomes-based loans). Automatic Payment Discount is available if the borrower is enrolled in automatic payments from their personal checking account and the amount is successfully withdrawn from the authorized bank account each month. For Ascent rates and repayment examples please visit: AscentFunding.com/Rates. 1% Cash Back Graduation Reward subject to terms and conditions. Cosigned Credit-Based Loan student must meet certain minimum credit criteria. The minimum score required is subject to change and may depend on the credit score of your cosigner. Lowest rates require full
principal and interest payments, the shortest loan term, a cosigner, and are only available for our most creditworthy applicants and cosigners with the highest average credit scores. Actual APR offered may be higher or lower than the repayment examples above, based on the amount of time you spend in school and any grace period you have before repayment begins.

5.66 - 15.16%
lender LendKey logo
LendKey
Minimum credit score
660
Fixed APR
Fixed APR

1 – Terms and Conditions Apply

Loan products, terms, and benefits may be modified or discontinued by participating lenders at any time without notice. Rates displayed are reserved for the most creditworthy consumers who enroll to make automatic monthly payments. Your initial rate will be determined after a review of your application and credit profile. Variable rates may increase after consummation. You must be either a U.S. citizen or Permanent Resident in an eligible state and from an eligible school, and meet the lender’s credit and income requirements to qualify for a loan. Certain membership requirements (including the opening of a share account, a minimum share account deposit, and the payment of any applicable association fees in connection with membership) may apply in the event that an applicant wishes to apply with, and accept a loan offered from, a credit union lender. If you are not a member of the credit union lender, you may apply and become a member during the loan application process if you meet the lender’s eligibility criteria. Applying with a creditworthy cosigner may result in a better chance of loan approval and/or lower interest rate. Loans for exam preparation classes, including, but not limited to, loans for LSAT, MCAT, GMAT, and GRE preparation, are not available via LendKey.com.

2 – Cosigner Release

Some lenders participating on LendKey.com may offer the benefit of cosigner release. Cosigner release is subject to lender approval. In order to qualify, the borrower, alone, must meet the following requirements: (1) Make the required number of consecutive, on-time full principal and interest payments as indicated in the borrower’s credit agreement during the repayment period (excluding interest-only payments) immediately prior to the request. Any period of forbearance will reset the repayment clock; (2) The account cannot be in delinquent status; (3) The borrower must provide proof of income indicating that he/she meets the income requirements and pass a credit review demonstrating that he/she has a satisfactory credit history and the ability to assume full responsibility of loan repayment; (4) No bankruptcies or foreclosures in the last sixty months; and (5) No loan defaults.

3 – Autopay Rate Reduction

Subject to floor rate and may require the automatic payments be made from a checking or savings account with the lender. The rate reduction will be removed and the rate will be increased by 0.25% upon any cancellation or failed collection attempt of the automatic payment and will be suspended during any period of deferment or forbearance. As a result, during the forbearance or suspension period, and/or if the automatic payment is canceled, any increase will take the form of higher payments.

4 – AutoPay Discount & Lowest Interest Rate

Subject to floor rate and may require the automatic payments be made from a checking or savings account with the lender. The rate reduction will be removed and the rate will be increased by 0.25% upon any cancellation or failed collection attempt of the automatic payment and will be suspended during any period of deferment or forbearance. As a result, during the forbearance or suspension period, and/or if the automatic payment is canceled, any increase will take the form of higher payments. The lowest advertised APR is only available for loan terms of 10 years and is reserved for the highest qualified applicants, taking into consideration the applicant’s credit and other factors.

3.99 - 12.61%
Variable APR
Variable APR

1 – Terms and Conditions Apply

Loan products, terms, and benefits may be modified or discontinued by participating lenders at any time without notice. Rates displayed are reserved for the most creditworthy consumers who enroll to make automatic monthly payments. Your initial rate will be determined after a review of your application and credit profile. Variable rates may increase after consummation. You must be either a U.S. citizen or Permanent Resident in an eligible state and from an eligible school, and meet the lender’s credit and income requirements to qualify for a loan. Certain membership requirements (including the opening of a share account, a minimum share account deposit, and the payment of any applicable association fees in connection with membership) may apply in the event that an applicant wishes to apply with, and accept a loan offered from, a credit union lender. If you are not a member of the credit union lender, you may apply and become a member during the loan application process if you meet the lender’s eligibility criteria. Applying with a creditworthy cosigner may result in a better chance of loan approval and/or lower interest rate. Loans for exam preparation classes, including, but not limited to, loans for LSAT, MCAT, GMAT, and GRE preparation, are not available via LendKey.com.

2 – Cosigner Release

Some lenders participating on LendKey.com may offer the benefit of cosigner release. Cosigner release is subject to lender approval. In order to qualify, the borrower, alone, must meet the following requirements: (1) Make the required number of consecutive, on-time full principal and interest payments as indicated in the borrower’s credit agreement during the repayment period (excluding interest-only payments) immediately prior to the request. Any period of forbearance will reset the repayment clock; (2) The account cannot be in delinquent status; (3) The borrower must provide proof of income indicating that he/she meets the income requirements and pass a credit review demonstrating that he/she has a satisfactory credit history and the ability to assume full responsibility of loan repayment; (4) No bankruptcies or foreclosures in the last sixty months; and (5) No loan defaults.

3 – Autopay Rate Reduction

Subject to floor rate and may require the automatic payments be made from a checking or savings account with the lender. The rate reduction will be removed and the rate will be increased by 0.25% upon any cancellation or failed collection attempt of the automatic payment and will be suspended during any period of deferment or forbearance. As a result, during the forbearance or suspension period, and/or if the automatic payment is canceled, any increase will take the form of higher payments.

4 – AutoPay Discount & Lowest Interest Rate

Subject to floor rate and may require the automatic payments be made from a checking or savings account with the lender. The rate reduction will be removed and the rate will be increased by 0.25% upon any cancellation or failed collection attempt of the automatic payment and will be suspended during any period of deferment or forbearance. As a result, during the forbearance or suspension period, and/or if the automatic payment is canceled, any increase will take the form of higher payments. The lowest advertised APR is only available for loan terms of 10 years and is reserved for the highest qualified applicants, taking into consideration the applicant’s credit and other factors.

5.98 - 13.74%
lender Earnest logo
Earnest
Minimum credit score
650
Fixed APR
Fixed APR

Student Loan Origination (Private Student Loan) Interest Rate Disclosure:

Actual rate and available repayment terms will vary based on your income. Fixed rates range from 3.94% APR to 16.74% APR (excludes 0.25% Auto Pay discount). Variable rates range from 5.87% APR to 17.10% APR (excludes 0.25% Auto Pay discount). Earnest variable interest rate student loan origination loans are based on a publicly available index, the 30-day Average Secured Overnight Financing Rate (SOFR) published by the Federal Reserve Bank of New York. The variable rate is based on the rate published on the 25th day, or the next business day, of the preceding calendar month, rounded to the nearest hundredth of a percent. The rate will not increase more than once per month. Although the rate will vary after you are approved, it will never exceed 36% (the maximum allowable for this loan). Please note, Earnest Private Student Loans are not available in Nevada. Our lowest rates are only available for our most credit qualified borrowers and contain our .25% auto pay discount from a checking or savings account. It is important to note that the 0.25% Auto Pay discount is not available while loan payments are deferred.
Earnest Private Student Loans are made by One American Bank, Member FDIC, or FinWise Bank, Member FDIC. One American Bank, 515 S. Minnesota Ave, Sioux Falls, SD 57104. Finwise Bank, 756 East Winchester, Suite 100, Murray, UT 84107
Earnest loans are serviced by Earnest Operations LLC, 535 Mission St., Suite 1663 San Francisco, CA 94105, NMLS #1204917, with support from Higher Education Loan Authority of the State of Missouri (MOHELA) (NMLS# 1442770). One American Bank, FinWise Bank, and Earnest LLC and its subsidiaries, including Earnest Operations LLC, are not sponsored by agencies of the United States of America. © 2024 Earnest LLC. All rights reserved.
3.69 - 16.49%
Variable APR
Variable APR

Student Loan Origination (Private Student Loan) Interest Rate Disclosure:

Actual rate and available repayment terms will vary based on your income. Fixed rates range from 3.94% APR to 16.74% APR (excludes 0.25% Auto Pay discount). Variable rates range from 5.87% APR to 17.10% APR (excludes 0.25% Auto Pay discount). Earnest variable interest rate student loan origination loans are based on a publicly available index, the 30-day Average Secured Overnight Financing Rate (SOFR) published by the Federal Reserve Bank of New York. The variable rate is based on the rate published on the 25th day, or the next business day, of the preceding calendar month, rounded to the nearest hundredth of a percent. The rate will not increase more than once per month. Although the rate will vary after you are approved, it will never exceed 36% (the maximum allowable for this loan). Please note, Earnest Private Student Loans are not available in Nevada. Our lowest rates are only available for our most credit qualified borrowers and contain our .25% auto pay discount from a checking or savings account. It is important to note that the 0.25% Auto Pay discount is not available while loan payments are deferred.
Earnest Private Student Loans are made by One American Bank, Member FDIC, or FinWise Bank, Member FDIC. One American Bank, 515 S. Minnesota Ave, Sioux Falls, SD 57104. Finwise Bank, 756 East Winchester, Suite 100, Murray, UT 84107
Earnest loans are serviced by Earnest Operations LLC, 535 Mission St., Suite 1663 San Francisco, CA 94105, NMLS #1204917, with support from Higher Education Loan Authority of the State of Missouri (MOHELA) (NMLS# 1442770). One American Bank, FinWise Bank, and Earnest LLC and its subsidiaries, including Earnest Operations LLC, are not sponsored by agencies of the United States of America. © 2024 Earnest LLC. All rights reserved.
5.62 - 16.85%
lender College Ave logo
College Ave
Minimum credit score
Mid-600s
Fixed APR
Fixed APR

College Ave Student Loans products are made available through Firstrust Bank, member FDIC, First Citizens Community Bank, member FDIC, or M.Y. Safra Bank, FSB, member FDIC. All loans are subject to individual approval and adherence to underwriting guidelines. Program restrictions, other terms, and conditions apply.

(1) All rates include the auto-pay discount. The 0.25% auto-pay interest rate reduction applies as long as a valid bank account is designated for required monthly payments. If a payment is returned, you will lose this benefit. Variable rates may increase after consummation.

(2) As certified by your school and less any other financial aid you might receive. Minimum $1,000.

(3) This informational repayment example uses typical loan terms for a freshman borrower who selects the Flat Repayment Option with an 8-year repayment term, has a $10,000 loan that is disbursed in one disbursement and a 7.78% fixed Annual Percentage Rate (“APR”): 54 monthly payments of $25 while in school, followed by 96 monthly payments of $176.21 while in the repayment period, for a total amount of payments of $18,266.38. Loans will never have a full principal and interest monthly payment of less than $50. Your actual rates and repayment terms may vary.

Information advertised valid as of 11/1/2024. Variable interest rates may increase after consummation. Approved interest rate will depend on creditworthiness of the applicant(s), lowest advertised rates only available to the most creditworthy applicants and require selection of the Flat Repayment Option with the shortest available loan term.

3.59 - 17.99%
Variable APR
Variable APR

College Ave Student Loans products are made available through Firstrust Bank, member FDIC, First Citizens Community Bank, member FDIC, or M.Y. Safra Bank, FSB, member FDIC. All loans are subject to individual approval and adherence to underwriting guidelines. Program restrictions, other terms, and conditions apply.

(1) All rates include the auto-pay discount. The 0.25% auto-pay interest rate reduction applies as long as a valid bank account is designated for required monthly payments. If a payment is returned, you will lose this benefit. Variable rates may increase after consummation.

(2) As certified by your school and less any other financial aid you might receive. Minimum $1,000.

(3) This informational repayment example uses typical loan terms for a freshman borrower who selects the Flat Repayment Option with an 8-year repayment term, has a $10,000 loan that is disbursed in one disbursement and a 7.78% fixed Annual Percentage Rate (“APR”): 54 monthly payments of $25 while in school, followed by 96 monthly payments of $176.21 while in the repayment period, for a total amount of payments of $18,266.38. Loans will never have a full principal and interest monthly payment of less than $50. Your actual rates and repayment terms may vary.

Information advertised valid as of 11/1/2024. Variable interest rates may increase after consummation. Approved interest rate will depend on creditworthiness of the applicant(s), lowest advertised rates only available to the most creditworthy applicants and require selection of the Flat Repayment Option with the shortest available loan term.

5.34 - 17.99%

Final Thoughts from the Nest

Interest is almost always part of taking out a student loan. Making educated decisions about what loans you take out and the interest rates associated with them is the most important piece to this equation. Always be sure to compare your loan options before agreeing to any one lender.

If you already have a student loan and struggling to make payments or think you may be able to get a lower interest rate, it may be time to consider refinancing.

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