The ceiling is frozen and the phase-out band is frozen too, which is a detail almost no summary carries. Section 221(f)(1) provides an inflation adjustment, but it reaches only "the $50,000 and $100,000 amounts in subsection (b)(2)" — the points at which the phase-out begins. The $2,500 maximum in subsection (b)(1) is outside the adjustment, and so is the width of the phase-out itself, which section 221(b)(2)(B)(ii) fixes at $15,000, or $30,000 on a joint return. So the starting point moves most years while the ceiling and the window do not, and both the benefit and the range over which it disappears shrink in real terms every year they go untouched.
Four conditions in the statute disqualify people who assume they qualify. Section 221(c) denies the deduction to an individual if a section 151 deduction with respect to that individual is allowed to another taxpayer, which is the dependent bar and which catches undergraduates paying their own interest. The condition turns on the claim actually being made rather than on eligibility to make it, so a student whose parents are entitled to claim them but do not is not caught by it. Section 221(e)(2) requires a married taxpayer to file jointly, so married filing separately produces no deduction whatsoever. Section 221(d)(1) requires that the debt have been incurred solely to pay qualified higher education expenses. And the same paragraph excludes a loan from a related person and a loan under a qualified employer plan, so borrowing from family or from a 401(k) to pay for education, or to clear education debt, ends the deduction on that money.
A refinance qualifies, and this is one of the few places the tax code is generous about a transaction that costs a borrower elsewhere. The concluding sentence of section 221(d)(1) says the term "includes indebtedness used to refinance indebtedness which qualifies as a qualified education loan." So the deduction survives a private refinance of a federal loan, even though nearly every other federal protection does not. The condition is that the original debt qualified: refinancing cannot bring a non-qualifying loan into the definition.
The expense definition here is frozen at 1997, and it is not the definition used on an aid letter. Section 221(d)(2) defines qualified higher education expenses by reference to cost of attendance under section 472 of the Higher Education Act "as in effect on the day before the date of the enactment of the Taxpayer Relief Act of 1997." The current statutory version of cost of attendance, rewritten by the FAFSA Simplification Act, is a different text, and section 529 freezes its own cross-reference at a third date. Three vintages of the same phrase are therefore in play across the education provisions, and treating the aid office's figure as the one section 221 uses is a mistake.
What counts as interest is broader than the number on a payment schedule. Treasury Regulation section 1.221-1(f) treats capitalized interest and loan origination fees that represent charges for the use or forbearance of money as interest, and the IRS instructions for Form 1098-E require a lender to include both in the reported amount for loans made on or after September 1, 2004. So an origination fee deducted from a disbursement is deductible interest, spread as the regulation provides, which is a real amount most borrowers never claim.
Two double-benefit rules sit at section 221(e)(1). Interest that an employer paid on the borrower's behalf and that the borrower excluded from income under section 127 is not also deductible, and a section 529 distribution used to repay a loan reduces the interest available for the deduction to the extent it would otherwise have been includible. One payment, one benefit, is the general principle running through the education provisions, and it applies here as much as it does to the credits.
Who may take it depends on who is legally obliged to pay, not on whose money moves. Treasury Regulation section 1.221-1(b)(1) allows the deduction only to a taxpayer with a legal obligation to make the interest payments under the terms of the loan. But section 1.221-1(b)(4) then supplies the rule that decides most family cases: where a third party who is not obliged on the loan pays interest on behalf of someone who is, the obligated taxpayer is treated as receiving that payment and paying the interest. So a parent who pays a graduate's loan is making a deductible payment for the graduate, and the graduate claims it.
The two rules interact badly in exactly one configuration. Where the student is the only obligor and is also claimed as somebody's dependent, the regulation's own Example 2 works it through: the student is barred by the dependent rule and the paying parent is barred for lack of a legal obligation, so nobody deducts the interest. That is the case to plan around, and it turns on whose name went on the note and whether the dependency claim is made, rather than on who makes the payments later.
