Student loan interest goes on Line 21 of Schedule 1 (Form 1040), under Part II, “Adjustments to Income.” The deduction is capped at $2,500 per year and reduces your adjusted gross income before the standard or itemized deduction, so you get the benefit whether you itemize or not.1Internal Revenue Service. Topic No. 456, Student Loan Interest Deduction
How the Amount Moves From Schedule 1 to Form 1040
After you enter your deductible interest on Line 21, add up every adjustment in Part II of Schedule 1 and put the total on Line 26. That figure transfers to Form 1040 (or 1040-SR), Line 10. On the main form, Line 10 is subtracted from your total income on Line 9 to produce your adjusted gross income on Line 11.2Internal Revenue Service. 2025 Schedule 1 (Form 1040)
Tax software handles the transfer automatically once you enter the interest or import a Form 1098-E. Confirm that Line 21 actually shows a number before you file, because the program can only work with what you gave it.
Figuring the Number That Goes on Line 21
If you paid $600 or more in student loan interest during the year, your servicer sends you Form 1098-E by early February. Box 1 is the total interest the servicer received. With more than one servicer, add up Box 1 from every 1098-E.3Internal Revenue Service. About Form 1098-E, Student Loan Interest Statement
You can still claim the deduction with no 1098-E, either because you paid less than $600 or because the form never arrived. Total the interest from your account statements yourself. The number you enter on Line 21 cannot exceed $2,500 even if you paid more.
Two categories of deductible interest are easy to miss when you’re tallying it up:
- Loan origination fees charged for the use of money accrue as interest over the life of the loan. Divide the fee by the number of months in the loan term to get the monthly amount, and deduct only the portion attributable to the tax year.
- Capitalized interest — unpaid interest your servicer folds into principal after a deferment or forbearance — becomes deductible interest as you pay down the inflated principal. You get no deduction for capitalized interest in any year you made zero payments.4Internal Revenue Service. Publication 970 (2025), Tax Benefits for Education
Forms issued for loans originated before September 2004 may report only stated interest, leaving origination fees and capitalized interest out of Box 1. In that case you calculate those pieces separately and add them to what the 1098-E shows.
When Income Reduces What You Can Put on Line 21
The full $2,500 is available only if your modified adjusted gross income stays below an inflation-adjusted threshold. For 2025, the deduction begins phasing out at $85,000 for single filers and $170,000 for joint filers, and disappears entirely at $100,000 and $200,000.4Internal Revenue Service. Publication 970 (2025), Tax Benefits for Education
Inside the phase-out range, the deduction is reduced, not eliminated. Multiply $2,500 by a fraction: MAGI above the lower threshold, divided by $15,000 (single) or $30,000 (joint). Subtract the result from $2,500. That reduced number is what goes on Line 21. The Student Loan Interest Deduction Worksheet in the Schedule 1 instructions walks through the math.
MAGI for this purpose is your AGI figured without the student loan interest deduction itself, plus any foreign earned income exclusion, foreign housing exclusion or deduction, and income exclusions for residents of American Samoa or Puerto Rico. For most domestic borrowers, MAGI equals AGI before the deduction.
Who Cannot Use Line 21 at All
Three situations disqualify you entirely, regardless of how much interest you paid:
- You file married filing separately. MFS filers are barred from the deduction.
- Someone else claims you as a dependent on their return.
- You are not legally obligated on the loan. Your name has to be on the promissory note as borrower or co-signer.5Office of the Law Revision Counsel. 26 U.S. Code 221 – Interest on Education Loans
If any of those apply, Line 21 stays blank.
Refinanced and Consolidated Loans
Refinancing a qualified student loan does not disqualify the interest. The statute covers debt used to refinance a qualified education loan, so interest on the new loan remains deductible as long as the original loan met the requirements. Federal consolidation loans work the same way.5Office of the Law Revision Counsel. 26 U.S. Code 221 – Interest on Education Loans The exception is when student debt gets rolled into a general-purpose loan such as a home equity loan. Once the original student loan is replaced by that kind of instrument, the interest no longer qualifies for Line 21.
Records to Keep After You File
Hold onto Form 1098-E, monthly loan statements, and any worksheets you used to compute origination fees or capitalized interest. The IRS generally requires records supporting a deduction for at least three years from the date you filed the return or two years from the date you paid the tax, whichever is later.6Internal Revenue Service. How Long Should I Keep Records
If You Enter It Wrong
Claiming the deduction when you don’t qualify can trigger an accuracy-related penalty of 20% of the resulting tax underpayment. The IRS applies it for negligence or for a substantial understatement of tax.7Internal Revenue Service. Accuracy-Related Penalty Interest runs on top of the penalty from the original due date, and the IRS cannot waive that interest even if it reduces the penalty. If you realize Line 21 was wrong after you filed, an amended return is the cleanest fix.