Is HELOC interest tax deductible?
The 2026 rules, plainly.

A HELOC has been marketed as tax-advantaged financing for decades. In 2026, for most homeowners, the tax benefit has disappeared. Before 2018, interest on up to $100,000 of home-equity debt was deductible regardless of use: credit cards, tuition, a car, a vacation. The 2017 Tax Cuts and Jobs Act (TCJA) replaced that blanket rule with a narrower one: HELOC interest is deductible only when the money is used to buy, build, or substantially improve the home that secures the loan. The rule was scheduled to sunset at the end of 2025; it did not. On July 4, 2025, the One Big Beautiful Bill Act (Public Law 119-21) made the TCJA HELOC rules permanent.

What follows is the operational version: what counts as a substantial improvement, how the $750,000 cap works when you have both a first mortgage and a HELOC, and what the IRS requires when HELOC funds are mixed between qualifying and non-qualifying uses. The largest filter on the deduction is not any of those specific rules. It is the standard-deduction threshold, which keeps about 90% of U.S. taxpayers from itemizing at all, and therefore from getting any HELOC-interest benefit even when every borrowed dollar went to a qualifying renovation.

The three conditions

Three rules, all of which must hold at the same time. Miss any one and the HELOC interest deduction is worth zero, regardless of what the HELOC was spent on.

Tax Policy Center data: in 2017, before TCJA raised the standard deduction, 31% of U.S. tax returns itemized. By 2022 that share had fallen to 9.5%. Roughly nine out of ten American taxpayers now take the standard deduction and get nothing from any itemized deduction, including the HELOC interest deduction. The drop was not driven by the HELOC rules changing; it was driven by the standard deduction roughly doubling overnight. For most HELOC borrowers, the tax argument for the product was already gone before the HELOC-specific rules tightened.

What counts as “substantially improve”

The qualifying-use rule comes from IRS Publication 936 and the underlying Internal Revenue Code section — IRC §163(h), for anyone wanting the statute. Publication 936 defines a substantial improvement as one that “adds value, prolongs useful life, or adapts the home to new uses.” The IRS has never published an exhaustive list, which is how tax law usually works — determinations are case-by-case. But the line between improvement and repair is well-traced in practice.

• Clearly qualifies: kitchen or bathroom remodel; room addition; new roof (replacement, not just patching); HVAC system replacement; solar panel installation; finished basement; new windows throughout; deck or patio addition; accessory dwelling unit (ADU); structural repairs after damage; upgrades for accessibility or aging in place.
• Clearly does not qualify: painting alone; carpet cleaning; appliance repair (replacement as part of a kitchen remodel is different); patching gutters, floors, or leaks; landscape maintenance; annual service on existing HVAC; general upkeep. These are classified as repairs or maintenance, which don’t add value in the tax sense.
• Gray areas: appliance replacement as a standalone project (often repair); driveway resurfacing (maintenance) vs. replacement (improvement); landscape hardscaping (usually qualifies) vs. landscape plantings (usually doesn’t); partial room remodels. For gray cases, the determining question is whether the work meaningfully extends the home’s useful life or adapts it to new uses — not whether it cost money.

The distinction matters because HELOCs are often used for mixed projects. A homeowner drawing $50,000 to redo a kitchen plus repaint the rest of the house runs into the rule immediately: the kitchen portion qualifies, the painting portion does not. The IRS allocates by where each dollar went, not by what the loan is secured against.

The $750,000 combined cap

The second-most-misread rule. The $750,000 cap ($375,000 for married filing separately) applies to the combined balance of the first mortgage plus any HELOC or home equity loan used for qualifying improvements — not just to the HELOC in isolation. Grandfathered exception: mortgages originated on or before December 15, 2017, keep the old $1 million cap (plus $500,000 if married filing separately).

Three scenarios show the arithmetic.

In San Francisco, Manhattan, Los Angeles, and Seattle, median home prices produce mortgage balances that regularly clear $750,000 for primary-residence buyers. The deduction referenced in lender marketing is usually not available to those buyers at all.

Mixed-use draws and the tracing rule

The most technical part of the rules. Under Treasury Regulation §1.163-8T — a temporary regulation on interest-expense allocation — the IRS looks through the loan to where the money actually went. A HELOC used partly for a renovation and partly for something else isn’t a “partly deductible HELOC.” It’s a loan whose interest must be allocated, dollar by dollar, to the actual uses of the proceeds.

Example. A borrower draws $60,000 from a HELOC into a checking account. $40,000 goes to a kitchen contractor. $20,000 pays off credit cards. At 7.02%, the full-year interest is about $4,284. The deductible portion is two-thirds — roughly $2,856 — reflecting the $40,000 that went to the qualifying improvement. The other $1,428, covering the $20,000 that went to credit cards, is not deductible at all. Claiming the full $4,284 as a deduction is overclaiming.

The practical problem is documentation. Once HELOC funds hit a checking account, they commingle with other money. Proving which dollars went where requires bank statements, contractor invoices, cancelled checks, and often a spreadsheet tying each HELOC draw to specific expenditures. The IRS provides a “safe harbor” under Notice 89-35: any expenditure made within 30 days before or 30 days after receiving loan proceeds can be treated as made from those proceeds, regardless of which account the money flowed through. That 60-day window is the most useful concession for borrowers who don’t want to run a dedicated HELOC bank account just to keep funds segregated.

For borrowers expecting a large number of smaller draws (a multi-phase renovation over two years, say), a dedicated bank account holding only HELOC money and paying only qualifying expenses is the cleanest approach. Deductibility is determined by where the cash actually landed, not by the loan's label.

The itemization gatekeeper

The largest filter on the HELOC deduction is also the one least often discussed. A taxpayer can only deduct HELOC interest by itemizing on Schedule A, listing all itemized deductions individually and using that total instead of the standard deduction. For 2026, the standard deduction is $32,200 for married couples filing jointly, $24,150 for heads of household, and $16,100 for single filers. The OBBBA made those inflation-adjusted levels permanent.

The practical consequence. To benefit from a HELOC interest deduction, a borrower’s total itemizable deductions — primarily mortgage interest, state and local taxes (capped at $40,000 under OBBBA for most filers), charitable contributions, and a handful of smaller items — have to exceed the standard deduction. For most middle-income homeowners with a moderate mortgage, the math doesn’t get there. Tax Policy Center data: about 90% of U.S. tax returns now take the standard deduction.

Who actually benefits, in practice:

• High-income taxpayers. The itemization rate rises sharply with income. Households above $500,000 in adjusted gross income itemize at roughly 65% — a function of their larger mortgages, larger SALT bills, and larger charitable giving.
• Homeowners in high-tax states (California, New York, New Jersey, Connecticut, Illinois, Massachusetts). Large mortgages and large state-income and property-tax bills stack toward the SALT cap. Combined with mortgage interest, the total often clears the standard-deduction threshold.
• Taxpayers with significant charitable giving who are already itemizing for that reason. For them, adding HELOC interest is incremental.

For the roughly 90% of taxpayers taking the standard deduction, the HELOC tax deduction should not drive the product choice. Pick the product based on rate, terms, and use case; for most readers, the tax benefit is zero.

Documentation and audit risk

The documentation burden on a HELOC interest deduction is heavier than it looks. The IRS requires, on audit, that the borrower prove three things: legal responsibility for the debt, that the debt meets the tax code's definition of qualifying acquisition indebtedness (Section 163(h) of the Internal Revenue Code), and that the interest being claimed was actually paid. A 2016 Tax Court decision upheld the IRS's denial of a $66,354 mortgage interest deduction for a 2012 return when the taxpayer could not produce adequate documentation. The deduction was not disallowed as fraudulent; it was disallowed for lack of proof.

The documentation to keep, for as long as you own the home plus at least seven years after:

• Form 1098 from the lender each year, showing the HELOC interest paid. This is the starting point for the deduction.
• The HELOC loan agreement proving the loan is secured by the qualified residence.
• Contractor contracts, invoices, and cancelled checks proving that HELOC funds were used for qualifying improvements. Itemization matters — a single lump invoice is weaker than a detailed one.
• Building permits, where applicable. Permits distinguish improvements (permit required) from most repairs (no permit) in the IRS’s analysis.
• Bank statements showing each HELOC draw and tracing those funds to the improvement expenses. This is the core of the tracing documentation under Treasury Reg §1.163-8T.
• Before-and-after photos supporting the “substantial improvement” characterization. Not required but highly persuasive on audit.

A useful secondary benefit of this documentation: renovation costs also increase the home’s adjusted cost basis, which reduces taxable capital gain when the home is later sold. For long-term homeowners in appreciating markets whose gain might exceed the $250,000 (single) or $500,000 (joint) primary-residence exclusion, the basis adjustment can be worth as much as the annual interest deduction — sometimes more. Keep the renovation receipts either way.

The short version

The HELOC interest deduction in 2026 is narrower than most lender marketing suggests. Three conditions must hold together: the funds must be used to buy, build, or substantially improve the home; the taxpayer must itemize rather than take the standard deduction; and combined mortgage-plus-HELOC debt must stay under $750,000. The One Big Beautiful Bill Act made all three rules permanent in July 2025, so the old blanket home-equity deduction is not coming back. The standard-deduction threshold is the biggest filter and removes about 90% of U.S. taxpayers from any possible benefit. For a high-income homeowner in a high-tax state using a HELOC on a real renovation, the deduction is still worth real money. For everyone else, the HELOC decision should be made on rate, terms, and use. The tax benefit, for most readers, is zero.

Common questions

Is HELOC interest deductible if I use the money on a rental property?

Not as home-mortgage interest. The home-mortgage-interest rules require HELOC funds to be used on the home that secures the loan — so a HELOC on your primary residence used to buy, improve, or fund a rental doesn’t qualify under the $750,000 cap. The interest may be deductible as an investment-property expense on Schedule E instead, since the funds financed an income-producing property. That’s a different deduction with different rules, and one worth confirming with a tax professional before claiming.

Is HELOC interest deductible on a second home?

Yes, if the HELOC is secured by the second home and the money is used to buy, build, or substantially improve that same home. A HELOC on your primary residence used for work on a second home doesn’t qualify — the collateral property and the improved property have to match. The $750,000 combined cap applies across your first and second homes together, not separately.

Do home repairs count as a “substantial improvement” for the deduction?

Usually not. The IRS draws a specific line: a “substantial improvement” adds to the home’s value, extends its useful life, or adapts it to new uses. Repairs that maintain existing condition don’t qualify — painting a room, patching drywall, replacing a broken appliance, annual HVAC service. Replacing a failing roof or a dead HVAC system does qualify because the replacement extends useful life. The cleanest test: if the work would be capitalized on a rental property’s tax return, it probably counts as a substantial improvement on yours.

Is HELOC interest deductible if I use it to pay off credit card debt?

No. The 2017 Tax Cuts and Jobs Act ended the blanket deduction for HELOC interest used on non-home-improvement purposes. Interest on a HELOC drawn to consolidate credit cards, pay off auto loans, fund tuition, or cover medical bills isn’t deductible — even though the lender still reports the full interest amount on Form 1098. The 1098 doesn’t establish deductibility; the use of funds does. See our guide on using a HELOC for debt consolidation for the full picture.

What tax form do I need to claim the HELOC interest deduction?

Form 1098 (Mortgage Interest Statement) from your HELOC lender, which arrives each January. The deduction itself goes on Schedule A of Form 1040, under “Home mortgage interest and points.” You also need records proving the funds were used for a qualifying purpose — contractor invoices, permits, and bank statements showing the HELOC draw flowing to the improvement. The IRS doesn’t ask for those at filing, but if you’re audited, the burden of proof is yours.