Homeowners who tapped a home-equity loan or line of credit to pay off credit cards, fund a vacation, or cover tuition bills lost the right to deduct that interest after the 2017 tax law change took effect. The IRS now permits the deduction only when borrowed funds go toward buying, building, or substantially improving the residence that secures the debt. That single condition, spelled out in federal statute and restated across multiple IRS publications for the 2025 filing year, determines whether thousands of dollars in annual interest payments reduce a filer’s taxable income or simply vanish as a nondeductible personal expense.
Why the Use-of-Proceeds Test Changed Everything After 2017
Before 2018, a homeowner could deduct interest on up to $100,000 of home-equity debt no matter how the money was spent. The Tax Cuts and Jobs Act eliminated that blanket treatment. Under 26 U.S.C. Section 163, personal interest is generally disallowed, and the surviving exception for “qualified residence interest” now covers only acquisition indebtedness, meaning debt used to acquire, construct, or substantially improve the qualifying home.
The IRS reinforced this distinction in a consumer-facing FAQ that compares the old and new rules in straightforward terms. After 2017, home-equity loan or HELOC interest qualifies for the deduction only if the proceeds are used to buy, build, or substantially improve the residence. That shift means the label on the loan product is irrelevant. A traditional mortgage used for debt consolidation fails the test, while a HELOC used to replace a roof passes it.
The practical consequence falls on the borrower at filing time. The 2025 instructions for Schedule A filers direct taxpayers to deduct home mortgage interest only to the extent that loan proceeds were used to buy, build, or substantially improve the securing home. When proceeds serve mixed purposes, part renovation and part personal spending, the filer must allocate interest between deductible and nondeductible portions. Ignoring that allocation risks losing the entire deduction if the IRS questions the return, especially if the taxpayer cannot show how the borrowed money was used.
How IRS Publications and Regulations Trace the Money
Three separate IRS publications now restate the same rule for different audiences. Publication 936, the agency’s detailed guide to home mortgage interest, is the primary reference for the 2025 tax year. It explains how to treat mixed-use proceeds, how to distinguish acquisition debt from other borrowing, and where to report the deduction on Schedule A. Publication 530, which focuses on homeowners more broadly, includes a caution that interest is deductible only to the extent proceeds were used for qualifying home improvements, and it points readers directly to Publication 936 for the line-by-line calculations.
Behind those consumer guides sits the regulatory framework in 26 C.F.R. Section 1.163-10T, which describes the interest-tracing and allocation mechanics that apply when loan proceeds fund different purposes. These temporary regulations instruct taxpayers and examiners to follow the money from the moment it is borrowed, assigning each dollar to a specific use such as home acquisition, home improvement, investment, or personal spending. If a single loan pays for both a kitchen remodel and a car purchase, the regulations require the interest to be split proportionally between deductible home-mortgage interest and nondeductible personal interest.
The Internal Revenue Manual, used by IRS personnel during examinations, mirrors this tracing approach. When an auditor reviews a return that claims a large mortgage interest deduction, the manual directs them to verify how the underlying loan proceeds were actually spent. Bank statements, closing documents, contractor invoices, and settlement sheets all become evidence in determining whether the use-of-proceeds test is satisfied. If the taxpayer cannot substantiate that borrowed funds went into the home that secures the loan, the examiner may reclassify part or all of the claimed deduction as personal interest and assess additional tax, penalties, and interest.
Recordkeeping and Planning Implications for Homeowners
The modern rules effectively turn every refinancing, cash-out transaction, and HELOC draw into a recordkeeping exercise. To protect the deduction, homeowners must be able to connect borrowed dollars to specific qualifying projects-such as additions, structural repairs, or major system upgrades-and distinguish those from nonqualifying uses. Maintaining a simple ledger that tracks each draw, date, and purpose, along with supporting receipts and contracts, can make the difference between a fully allowed deduction and a costly adjustment years later.
Planning ahead also matters. A homeowner who expects to use equity for both home improvements and personal expenses may want to separate those uses into different loans or distinct draws that are easy to trace. Keeping improvement-related funds in a dedicated account, rather than commingling them with everyday spending, simplifies the allocation exercise when it is time to complete Schedule A. In some cases, borrowers may decide that using home equity for non-housing purposes is less attractive once the loss of the interest deduction is factored into the true after-tax cost.
The bottom line is that the deduction for home-equity interest now depends far less on what the lender calls the loan and far more on what the borrower actually does with the money. By understanding the use-of-proceeds test, following the tracing rules, and keeping clean records, homeowners can still benefit from the mortgage interest deduction when they use their equity to invest back into the home that secures the debt.
