Introduction
For years, homeowners assumed that any interest paid on a home equity line of credit was automatically tax-deductible simply because the loan was secured by their house. That assumption stopped being reliable back in 2018, when the Tax Cuts and Jobs Act (TCJA) tightened the rules significantly — and for most of 2025, tax professionals and homeowners alike were bracing for those rules to expire, potentially reopening the door to unrestricted HELOC interest deductions in 2026.
That didn’t happen. On July 4, 2025, President Trump signed the One Big Beautiful Bill Act (OBBBA), and rather than letting the TCJA’s home equity provisions sunset as originally scheduled, Congress made the TCJA’s home equity provisions permanent, meaning there is no expiration date and the rules will govern 2026 taxes and all future tax years unless Congress acts again. This surprised a lot of people who had been planning around the assumption that the restrictions would lapse.
This guide walks through exactly what qualifies for the HELOC interest deduction in 2026, what doesn’t, how the debt limits work, and how to document your HELOC properly so you don’t lose a deduction you’re actually entitled to.
The Big Picture: What Changed and What Didn’t
Before the OBBBA passed, the general expectation was that these restrictions would end, allowing homeowners to once again deduct home equity interest regardless of how the money was used. Congress made a different choice, and the restrictive rules first introduced under the TCJA are now a permanent fixture of the tax code rather than a temporary provision.
Here’s the state of play for 2026:
| Provision | Rule for 2026 |
| Qualifying use requirement | Interest deductible only if funds buy, build, or substantially improve the home securing the loan |
| Combined debt limit (MFJ/Single) | $750,000 |
| Combined debt limit (Married Filing Separately) | $375,000 |
| Legacy debt (originated before Dec. 15, 2017) | May still qualify under the older $1 million limit |
| Deduction method | Must itemize on Schedule A — not available with the standard deduction |
| Sunset date | None — made permanent under OBBBA |
The single most important thing to understand: the deduction is now governed by how you use the money, not by what kind of loan product you have. A HELOC, a home equity loan, and a cash-out refinance are all treated identically for deductibility purposes. The IRS framework treats all mortgage debt the same way, with deductibility depending on whether the debt was used to acquire or improve the home rather than which mortgage product was chosen.
The Core Rule: “Buy, Build, or Substantially Improve”
This three-part test is the foundation of everything else in this article. HELOC interest is generally deductible only if you use the money to buy, build, or substantially improve the home that secures the loan — using it for things like credit card payoff, travel, or tuition usually doesn’t qualify.
Let’s break each qualifying category down with real examples.
“Buy” — Acquisition Debt
This applies when HELOC funds are used as part of the purchase transaction itself — for example, using a HELOC on an existing home to help fund the down payment or closing costs on a new home purchase, where the HELOC is secured by the home being used as collateral.
“Build” — New Construction
Interest qualifies when funds go toward ground-up construction of a qualified residence — think of a HELOC secured by your current home being used to fund construction of a second home or replacement dwelling.
“Substantially Improve” — The Category Most Homeowners Actually Use
This is where the vast majority of HELOC tax questions live. A “substantial improvement” generally means a renovation that adds value to the home, prolongs its useful life, or adapts it to new uses — not routine maintenance or repairs.
Qualifying improvements typically include:
- Kitchen or bathroom remodels
- Room additions or square footage expansion
- Roof replacement
- New HVAC systems
- Foundation repair tied to structural improvement
- Solar panel installation
- Major landscaping tied to structural work (retaining walls, drainage systems)
- Whole-home electrical or plumbing system upgrades
Non-qualifying uses, even though they’re common HELOC purposes:
- Paying off credit card debt
- Consolidating other personal loans
- Covering medical bills
- Funding a wedding or vacation
- Paying for college tuition
- Starting or funding a business
- Buying a car
- Covering everyday living expenses during a cash-flow gap
Common qualifying uses include home renovations, additions, roof replacements, or major system upgrades, while interest is not deductible when funds are used for things like paying off credit cards, consolidating personal debt, covering medical bills, or funding vacations — even though these may be financially practical uses of the money.
The $750,000 Debt Limit, Explained With Real Numbers
The deduction isn’t just about what you used the money for — it’s also capped by how much total qualifying mortgage debt you’re carrying across your first mortgage, home equity loan, and HELOC combined.
For loans originated after December 15, 2017, the combined acquisition debt limit is $750,000 for married filing jointly, or $375,000 for married filing separately, and this is the combined total of your first mortgage plus any qualifying home equity debt. Critically, if your primary mortgage already uses the full $750,000, additional HELOC interest is not deductible even if the HELOC funds are used for home improvement.
Example 1: Under the Limit
Sarah and Mike bought their home with a $500,000 mortgage. They later take out a $100,000 HELOC to renovate their kitchen and add a primary suite.
- Combined debt: $500,000 + $100,000 = $600,000
- This is under the $750,000 cap
- Result: Interest on the full HELOC is deductible, assuming funds are used entirely for the renovation, and they itemize
Example 2: Over the Limit
James has a $700,000 mortgage on his primary home. He opens a $150,000 HELOC to build a detached garage and finish a basement.
- Combined debt: $700,000 + $150,000 = $850,000
- This exceeds the $750,000 cap by $100,000
- Result: Only the interest attributable to the first $50,000 of the HELOC is deductible ($750,000 minus the existing $700,000 mortgage). Interest on the remaining $100,000 is not deductible, even though the money was used for a qualifying improvement.
Example 3: Legacy Debt Protection
Denise took out her mortgage in 2015, before the December 15, 2017 cutoff. Loans taken out on or before December 15, 2017 allow interest deductions on up to $1 million of home loan debt, regardless of how the funds are used. If she later adds a HELOC, the interaction between her grandfathered mortgage debt and any new HELOC debt gets more complex, and this is a scenario where consulting a tax professional is particularly important — the grandfathering generally applies to the original acquisition debt itself, not automatically to new HELOC debt layered on top of it.
Itemizing: The Step Everyone Forgets
Even if your HELOC checks every box above, none of it matters unless you itemize deductions on Schedule A. If you take the standard deduction, you cannot deduct HELOC interest, and to write off that interest you have to itemize deductions on Schedule A — which is why many homeowners don’t see a tax benefit from their HELOC even if the interest technically qualifies under IRS rules.
For the 2025 tax year (filed in 2026), the standard deduction is $15,750 for single filers and married filing separately filers, with higher figures for those married filing jointly and heads of household. Given how high the standard deduction has climbed, a growing share of homeowners find that their total itemized deductions — mortgage interest, HELOC interest, state and local taxes, charitable contributions — don’t actually exceed the standard deduction threshold. In those cases, the HELOC interest deduction provides no additional tax benefit, even though it’s technically “eligible.”
Quick Math: Should You Even Bother Itemizing?
| Deduction Category | Example Amount |
| Mortgage interest (first mortgage) | $14,000 |
| HELOC interest (qualifying use) | $3,200 |
| State and local taxes (SALT, capped) | $10,000 |
| Charitable contributions | $2,000 |
| Total itemized | $29,200 |
| Standard deduction (MFJ, 2025) | ~$31,500 |
In this example, even with a fully qualifying HELOC deduction, the total itemized amount still falls short of the standard deduction — meaning the household would take the standard deduction instead, and the HELOC interest deduction effectively provides zero additional tax savings. This is an increasingly common outcome and one of the most overlooked realities of HELOC tax planning.
Mixed-Use HELOCs: The Trickiest Scenario
Many homeowners don’t use their entire HELOC for a single purpose. It’s extremely common to draw funds for a kitchen remodel and then, a few months later, draw additional funds to cover a medical bill or pay down a credit card. This creates a mixed-use HELOC, and the IRS doesn’t let you deduct the whole thing just because part of it qualifies.
Mixed-use HELOCs require prorating, since only the home-improvement portion of the interest qualifies, and if you use part of your HELOC for a remodel and part for personal expenses, you must precisely allocate the interest between the two.
Real Numerical Example: Prorating Mixed-Use Interest
Tom opens a $60,000 HELOC. He draws:
- $40,000 for a bathroom renovation and new roof (qualifying)
- $20,000 to pay off credit card debt (non-qualifying)
Over the year, he pays $3,000 in total HELOC interest.
Qualifying proportion: $40,000 ÷ $60,000 = 66.7%
Deductible interest: $3,000 × 66.7% = $2,000
Non-deductible interest: $3,000 × 33.3% = $1,000
Tom can only claim $2,000 of the $3,000 in interest he paid. To support this on his tax return, he needs clear records tying each draw to its specific purpose — which brings us to documentation.
Documentation: What You Actually Need to Keep
This is the single most common way homeowners lose a legitimate deduction — not because the use didn’t qualify, but because they can’t prove it did if the IRS asks. Documentation is critical: to claim the deduction, you should keep all contractor invoices, receipts, permits, and bank statements showing HELOC funds went directly to home improvement.
Your HELOC Tax Documentation Checklist
- Form 1098 from your lender, showing total interest paid for the year
- Draw-by-draw records showing the date and amount of each HELOC withdrawal
- Contractor invoices and signed contracts for any renovation work
- Permits pulled for the improvement project, where applicable
- Bank statements showing the HELOC funds moving directly to the contractor, supplier, or project account (not to a general checking account where it becomes commingled)
- Before-and-after photos of the improvement (not required by the IRS, but useful supporting evidence)
- A written log mapping each draw to its specific purpose, especially for mixed-use HELOCs
The biggest documentation mistake homeowners make is depositing HELOC funds into a general checking account, using some of it for the renovation and some for other expenses, and then losing the ability to clearly trace which dollars went where. Where possible, keep HELOC funds in a separate account and pay contractors directly from that account to preserve a clean paper trail.
HELOCs vs. Home Equity Loans vs. Cash-Out Refinance: Same Tax Treatment
One point of confusion worth clearing up directly: the type of home equity product you choose doesn’t change the tax rules. The IRS treats HELOCs and home equity loans identically for deductibility purposes — both require qualifying use of proceeds for home improvements, both are subject to the $750,000 combined debt cap, and both require itemizing deductions. The loan structure differs (revolving line vs. lump sum), but the underlying tax rules are the same.
This also means a cash-out refinance is subject to the same acquisition-or-improvement test for the “cash-out” portion of the loan. If you refinance and pull out $50,000 to renovate, that $50,000 is treated the same way a HELOC draw for renovation would be treated.
Draw Period vs. Repayment Period: Does It Matter for Deductibility?
No — the timing of when interest accrues within your HELOC’s lifecycle doesn’t change whether it’s deductible. Interest paid during both the draw period and the repayment period is potentially deductible, provided the qualifying use and debt limit requirements are satisfied, because deductibility turns on how the funds were used, not on when in the loan lifecycle the interest accrues or is paid. Whether you’re three months into your draw period or five years into repayment, the same buy/build/improve test applies to every dollar borrowed.
Second Homes and Vacation Properties
The rules extend to second homes, not just your primary residence — but the same qualifying-use test applies, and the $750,000/$375,000 limit is a combined cap across all qualified residences, not a separate limit for each property.
Example: Combined Limit Across Two Homes
Rachel and David have:
- A primary home mortgage of $450,000
- A second home mortgage of $200,000
- A HELOC on their primary home of $150,000, used entirely to renovate the primary home’s kitchen
Combined debt: $450,000 + $200,000 + $150,000 = $800,000
This exceeds the $750,000 combined cap by $50,000, meaning interest on $50,000 of the HELOC balance is not deductible, even though the renovation itself fully qualifies as a substantial improvement.
Investment Properties: A Different Set of Rules Entirely
If your HELOC is secured by your primary residence but the funds are used to purchase, renovate, or improve a rental or investment property, the home mortgage interest deduction rules discussed throughout this article don’t apply at all. Instead, that interest may be deductible as a business expense against the rental property’s income, under an entirely different section of the tax code. This is a common point of confusion — homeowners assume the same buy/build/improve test governs investment property use, when in reality it’s governed by different rules tied to the property generating the income. If you’re using home equity for investment property purposes, this is a scenario to review specifically with a tax professional or CPA rather than relying on general HELOC guidance.
What Happens If You Later Change the Use of the Funds?
Deductibility is generally locked in based on how the funds were originally used at the time of the draw, not based on what you do with the renovated property later. However, complications can arise in specific scenarios:
- Selling the improved home shortly after the renovation: The deduction itself isn’t clawed back, but you’ll want records proving the improvement was made prior to any sale-related use-of-funds questions.
- Refinancing the HELOC into a new loan: If you refinance or consolidate a qualifying HELOC into a new loan product, the qualifying-use character generally carries over, but the new loan needs to be evaluated against the debt limit independently.
- Converting a primary residence to a rental: If you later convert the improved home into a rental property, the interest deduction may shift from the itemized home mortgage interest deduction to a rental expense deduction going forward.
Common Mistakes That Cost Homeowners Their Deduction
- Assuming any home-secured loan is automatically deductible. Product type doesn’t matter — use does.
- Commingling funds in a general checking account, making it impossible to trace which dollars paid for what.
- Not itemizing because the total doesn’t exceed the standard deduction — and not running the math to check.
- Forgetting the combined debt limit applies across all mortgage debt, not just the HELOC balance in isolation.
- Assuming renovations always count as “substantial improvements.” Routine repairs and maintenance — replacing a broken water heater, patching drywall, repainting — generally don’t rise to the level of a substantial improvement the way a full system replacement or addition does.
- Losing contractor documentation years before an audit could occur; the IRS generally has three years to audit a return, sometimes longer.
- Not consulting a tax professional on mixed-use draws, second-home scenarios, or investment property overlap, where the rules get materially more complex.
State Tax Considerations
Federal rules aside, some states have their own rules for mortgage and home equity interest deductions that may not mirror federal law exactly — a handful of states with income tax don’t conform fully to federal itemized deduction changes made by the TCJA and OBBBA. If you live in a state with income tax, it’s worth confirming with a state-specific tax resource or preparer whether your state treats HELOC interest deductibility differently than the federal rules outlined here.
Frequently Asked Questions
Is HELOC interest tax deductible in 2026? Yes, but only when the funds are used to buy, build, or substantially improve the home that secures the loan. Using the funds for debt consolidation, personal expenses, or anything unrelated to the home itself makes that portion of the interest non-deductible.
Did the tax rules for HELOC interest change for 2026? Not from what they were in 2025. The One Big Beautiful Bill Act made the TCJA’s home equity interest rules permanent starting in 2026, so the buy/build/improve restriction and the $750,000 debt limit continue without an expiration date.
What’s the maximum amount of debt I can deduct interest on? The combined mortgage and HELOC debt limit is $750,000 for joint filers and $375,000 for married filing separately, with some older, grandfathered mortgages potentially eligible under a higher $1 million limit.
Do I need to itemize to claim this deduction? Yes. You have to itemize deductions on Schedule A to write off HELOC interest — you can’t claim it if you take the standard deduction.
Can I deduct interest if I use my HELOC to pay off credit card debt? No. Interest on funds used for credit cards, tuition, or general daily expenses is not tax deductible under current rules.
What if I use part of my HELOC for renovations and part for something else? You’ll need to prorate the interest based on the percentage of funds used for qualifying versus non-qualifying purposes, and maintain documentation showing exactly how each draw was used.
Do home equity loans get treated differently than HELOCs for tax purposes? No. The tax rules are the same for both products — the loan structure differs, but deductibility depends on the same qualifying-use and debt-limit rules.
What documentation should I keep in case of an audit? Keep your Form 1098, draw-by-draw records, contractor invoices, permits, and bank statements clearly linking HELOC funds to the qualifying improvement.
Does it matter whether I’m in the draw period or repayment period of my HELOC? No. Interest is potentially deductible during both the draw period and repayment period, since deductibility depends on how the funds were used, not when the interest accrued.
Is this deduction permanent now, or could it change again? As of the OBBBA’s passage, there is no scheduled expiration date, meaning these rules are expected to remain in place for 2026 and future tax years unless Congress passes new legislation to change them.
Final Thoughts
The HELOC interest deduction survived a scare in 2025, but it survived in a more restrictive form than many homeowners originally had — permanently limited to funds used to buy, build, or substantially improve the home securing the loan, capped at $750,000 in combined mortgage debt, and only available to those who itemize. For homeowners using a HELOC specifically for renovations, the deduction can still provide meaningful tax savings, but it requires careful documentation, clean fund tracking, and an honest look at whether itemizing actually beats the standard deduction in your specific situation.
Because tax law interacts with your full financial picture — income level, filing status, state of residence, and other itemized deductions — this is genuinely a situation where a conversation with a CPA or tax preparer before drawing on a HELOC can save significant money and headaches at filing time.
