The student loan interest deduction: 2026 phase-out math

For three filing seasons, the student loan interest deduction was a line that quietly did nothing. From 2020 through 2023 the federal payment pause held interest at zero, so there was no interest to deduct, and the entry sat blank on millions of returns. That era is over. Interest is accruing again, which makes the 2026 filing season the first ordinary one in years where this small, easily missed adjustment is worth claiming — and worth understanding before your income quietly disqualifies you.

The deduction is generous in design and stingy in reach. You can subtract up to $2,500 of the interest you actually paid, you can do it without itemizing, and you take it right off the top of your income. But it fades as you earn more, on a sliding scale that the IRS resets for inflation each year, and it vanishes entirely above a ceiling that a dual-income household can clear faster than expected. Whether you get the full break, a sliver of it, or nothing at all is, like most things on this site, pure arithmetic.

For 2026 you can deduct up to $2,500 of student loan interest actually paid, as an above-the-line adjustment on Schedule 1 of Form 1040 — no itemizing required. The break phases out as modified adjusted gross income rises: for single and head-of-household filers it shrinks from $85,000 and is gone at $100,000 (a $15,000 window); for married filing jointly it runs from $175,000 to $205,000 (a $30,000 window). Married filing separately gets nothing. The allowed amount equals $2,500 × [1 − (MAGI − floor) / window], so a single filer at $92,500 — halfway through the band — keeps exactly $1,250.

What the deduction is, and why above-the-line matters

The student loan interest deduction lets you subtract the interest — never the principal — that you paid during the year on a qualified education loan, capped at $2,500. The cap is per return, not per loan, so two loans accruing $1,800 each still yield a single $2,500 maximum.

What makes it unusually friendly is where it lives on the return. It is an above-the-line deduction, meaning an adjustment to income reported on Schedule 1 of Form 1040 and subtracted before your adjusted gross income is even calculated. You do not have to itemize to claim it. That distinction matters because roughly nine in ten filers take the standard deduction, and an above-the-line deduction sits outside that standard-versus-itemized decision entirely — you get it either way. Mortgage interest and state taxes have to clear the standard-deduction bar before they save you a dollar; student loan interest does not.

Your servicer does the bookkeeping. If you paid $600 or more in interest during 2026, the lender sends you a Form 1098-E with the total in Box 1. If you paid less than $600, you will not get the form, but you can still deduct the interest as long as you have your own records — a payment history or year-end statement will do.

The 2026 phase-out, in numbers

The catch is income. The deduction does not cut off cleanly at a threshold; it erodes across a band, and the band depends on your filing status. The figures below come from IRS Revenue Procedure 2025-32, the annual inflation-adjustment release.

Filing status	Phase-out begins	Fully gone at	Window
Single / Head of Household	$85,000	$100,000	$15,000
Married Filing Jointly	$175,000	$205,000	$30,000
Married Filing Separately	Not allowed at any income	—	—

The income figure that matters here is modified adjusted gross income, or MAGI — your adjusted gross income with a few items added back, such as the foreign earned income exclusion. For most filers nothing gets added back, so MAGI is essentially equal to AGI; the full MAGI definition only diverges in narrow cases.

Inside the band, the deduction shrinks in proportion to how far you have traveled through it. The formula is straightforward:

allowed deduction = $2,500 × [1 − (MAGI − floor) / window]

A single filer at $92,500 sits exactly halfway through the $15,000 window. So the deduction is $2,500 × (1 − 0.5) = $1,250 — half the maximum, because they are half-phased-out. The arithmetic is the same at every income; only the fraction changes.

A worked example: a single filer at $90,000

Take a single borrower — call him Marcus — who paid the full $2,500 in student loan interest in 2026 and reports $90,000 of MAGI. He is over the $85,000 floor, so he does not get the whole deduction, but he is well short of the $100,000 ceiling, so he keeps a meaningful chunk.

The phase-out fraction is (90,000 − 85,000) / 15,000 = 33.3%. So Marcus has lost a third of the deduction and keeps two-thirds: $2,500 × (1 − 0.333) ≈ $1,667. That $1,667 is not money back — it is income he no longer pays tax on. In the 22% federal bracket, a $1,667 deduction is worth about $367 off his tax bill. Modest, but it is a form he was going to file anyway.

The table below walks a single filer across the band so you can see the slope:

Single-filer MAGI	Phased out	Allowed deduction (full $2,500 paid)
$80,000	0%	$2,500
$85,000	0%	$2,500
$90,000	33.3%	≈ $1,667
$92,500	50%	$1,250
$100,000 and up	100%	$0

Two things stand out. Below $85,000 the full deduction is intact, so a borrower hovering just over the floor sometimes finds that an ordinary pre-tax move — a larger 401(k) contribution, say — pulls MAGI back under $85,000 and restores the whole $2,500. And above $100,000 the line is simply zero; there is no partial credit for clearing the ceiling by a dollar.

The caveats that actually bite

Eligibility is narrower than the dollar cap suggests. To deduct the interest at all, you must be legally obligated to pay it — the loan has to be in your name, not a parent’s loan you happen to be helping with. The borrowed money must have gone toward qualified higher-education expenses for you, your spouse, or a dependent. And you cannot be claimed as someone else’s dependent: a graduate still on a parent’s return gets nothing here, even on a loan they pay themselves. The loan also cannot come from a relative or from a qualified employer retirement plan; those are carved out by statute.

Then there is the marriage penalty, and it is real. Because the phase-out runs on household MAGI, two earners who would each comfortably qualify as singles can be pushed clean over the $205,000 joint ceiling once they file together — losing the deduction precisely because they married. The single window tops out at $100,000 each, but the joint window stops at $205,000, not $200,000, and certainly not the $300,000 two unmarried filers could collectively reach. Married filing separately is no escape hatch, either: that status is barred from the deduction entirely, at any income.

One more boundary worth naming: this deduction is about interest you paid, not debt you erased. If you are mapping out a strategy for income-driven repayment plans or weighing whether to refinance federal loans into a private loan, the interest you pay along the way is what feeds this line — and the tax treatment of forgiven balances is a separate and far larger question covered in our piece on the student loan forgiveness tax bomb.

Who actually benefits in 2026

The deduction rewards the borrower in the broad middle: out of school, carrying real interest, earning enough to owe tax but not enough to phase out. A single filer under $85,000 with a four-figure interest bill gets the full $2,500 with no paperwork beyond a form their servicer already mailed. That is the cleanest case, and it is common.

It thins out from there. Single earners between $85,000 and $100,000, and couples between $175,000 and $205,000, get a shrinking fraction that is still worth claiming — a few hundred dollars for a form you are filing regardless. Above the ceilings, or filing separately, the deduction is gone, and no amount of recordkeeping changes that. The honest summary: it is small, it is easy, and it is the rare tax break that survives the standard deduction. Check Box 1 of your 1098-E, run the phase-out fraction, and take what the arithmetic allows.

Sources

• IRS — Topic No. 456, Student Loan Interest Deduction — the $2,500 cap, above-the-line treatment, eligibility rules, and the dependent and related-party exclusions.
• IRS — Publication 970, Tax Benefits for Education — qualified education loan and qualified expense definitions, the MAGI add-backs, and the Form 1098-E $600 reporting threshold.
• IRS — Revenue Procedure 2025-32 — the 2026 inflation-adjusted phase-out ranges: $85,000–$100,000 single and head of household, $175,000–$205,000 married filing jointly.

This is general information, not tax advice. Phase-out ranges adjust annually, your MAGI may differ from your AGI, and the figures here are illustrative — confirm your own numbers against your Form 1098-E and a current-year IRS source or a tax professional.