Robert Kim
Only about 13% of American taxpayers claimed the mortgage interest deduction in a recent filing year, down from around 32% just a decade earlier. That collapse didn’t happen because homeownership fell. It happened because the 2017 Tax Cuts and Jobs Act nearly doubled the standard deduction, quietly making the mortgage deduction worthless for most people who own a home.
That’s the thing nobody in the mortgage industry tells you upfront. They’ll hand you a flyer showing how much interest you’ll pay over 30 years, imply you can “write it all off,” and let you do the mental math wrong. I watched this happen constantly when I was underwriting loans. Borrowers genuinely believed the deduction was changing their financial picture in a meaningful way. For most of them, it wasn’t.
Let me show you exactly how this works, who it actually helps, and when you should stop counting on it.
- Only ~13% of taxpayers currently claim the mortgage interest deduction; most don't benefit.
- You must itemize deductions (Schedule A) to claim it, and most filers don't, because the standard deduction is higher.
- As of 2026, the deduction covers interest on up to $750,000 of mortgage principal (for loans originated after Dec. 15, 2017).
- A $400,000 mortgage at 7% yields roughly $27,800 in first-year interest, but the tax benefit depends entirely on your marginal rate and whether you itemize.
- High-income buyers in high-cost states (California, New York, Massachusetts) are far more likely to see real savings.
How the Deduction Actually Works
The mortgage interest deduction lets you subtract the interest you paid on a qualifying home loan from your taxable income. Not your taxes owed. Your taxable income. That distinction matters.
Say you’re in the 22% federal tax bracket and paid $14,000 in mortgage interest last year. If you can deduct that, you reduce your taxable income by $14,000, which cuts your tax bill by roughly $3,080. Not $14,000. $3,080.
But here’s where it gets messier. To claim that deduction, you have to itemize (that’s IRS Schedule A). And to make itemizing worthwhile, your total itemized deductions have to exceed the standard deduction. As of 2026, the standard deduction is $15,000 for single filers and $30,000 for married couples filing jointly. Those are big numbers to beat.
If your mortgage interest, state and local taxes (capped at $10,000), charitable contributions, and other deductible items don’t add up past those thresholds, the mortgage interest deduction gives you exactly nothing extra. You’d take the standard deduction anyway.
A borrower named Marcus, a reader who emailed me after buying a $325,000 home in suburban Columbus, Ohio, was furious when he realized this. He’d planned his budget around a $2,200 tax refund “from the mortgage interest.” His accountant told him in February that he and his wife would take the $30,000 standard deduction because their itemized total came to $22,400. The deduction he’d been counting on didn’t apply to a single dollar.
The $750,000 Cap and Who It Hits
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Loans originated after December 15, 2017 can only deduct interest on the first $750,000 of principal. (Older loans, originated before that date, are grandfathered at the old $1,000,000 cap.) So if you bought a $900,000 home with a $720,000 mortgage, you’re fine. But if you borrowed $850,000, you can only deduct interest on 88% of that balance.
This cap doesn’t hit most buyers in the Midwest or South, where median home prices are well below $750,000. It bites hardest in coastal metros where $900,000 barely buys a two-bedroom. The IRS doesn’t publish this breakdown by zip code, but the Tax Policy Center has shown that the top 20% of income earners capture the vast majority of benefits from this deduction. Which makes sense: they’re buying more expensive homes, they’re in higher tax brackets (so the deduction is worth more per dollar), and they’re far more likely to itemize.
Those figures assume $19,600 in first-year interest (7% on a $500,000 balance, rounded from actual amortization) and that the full amount is deductible above the standard deduction threshold. In practice, only the portion of itemized deductions exceeding the standard deduction gives you any marginal benefit, so the real savings for most people are smaller than even these numbers suggest.
Who Actually Benefits
Let’s be specific. Here’s what actually drives someone into “yes, this deduction matters” territory:
| Borrower Profile | Likely Benefit | Why |
|---|---|---|
| Married, $85K income, $300K loan, Ohio | Near zero | Standard deduction ($30K) exceeds itemized total |
| Single, $130K income, $600K loan, Texas | Modest ($2,000-$3,500) | May clear itemization threshold, 24% bracket |
| Married, $200K income, $700K loan, California | Meaningful ($5,000-$7,000+) | High state income tax pushes itemized total up |
| Single, $400K income, $900K loan, New York | Significant, but capped | $750K limit applies, 37% bracket, itemizes easily |
| Married, $70K income, $250K loan, Kansas | Zero | Standard deduction wins, no question |
The California and New York cases benefit partly because their high state income taxes (which are themselves deductible, up to the $10,000 SALT cap) push their itemized deductions over the standard deduction threshold. The mortgage interest then actually gets counted. It’s the combination of high state taxes plus high mortgage interest that makes the deduction meaningful.
I’ve run this math with probably a few dozen people informally over the years. The consistent pattern: if you’re in the Sun Belt, you probably don’t benefit. If you’re in a high-tax coastal state with a jumbo loan, you probably do.
The Refinance Wrinkle
Points paid to get a lower rate on a purchase loan can usually be deducted in full in the year you paid them. Points paid on a refinance have to be spread out over the loan term. That catches a lot of people.
Scenario: You refinance a $450,000 mortgage and pay 1.5 points ($6,750) to buy down your rate. You might expect to deduct that $6,750 this year. Instead, you deduct $6,750 divided by 360 months, or about $225 per month, meaning roughly $225 times 12 equals $2,700 for a partial year. A much smaller benefit than advertised.
There’s also the question of second homes. You can deduct mortgage interest on a second home, but the $750,000 cap applies across both loans combined. So if you have a $600,000 primary mortgage and a $250,000 vacation home mortgage, only $750,000 of that $850,000 combined balance counts.
Home equity loans are trickier. As of 2026, per IRS Publication 936, you can only deduct interest on a home equity loan if the money was used to “buy, build, or substantially improve” the home securing the loan. Using a HELOC to consolidate credit card debt or buy a car? That interest isn’t deductible, even if your lender sends you a 1098 form showing interest paid.
What the Data Says About the Deduction’s Real Impact
The Tax Policy Center estimated that in a recent year, the mortgage interest deduction cost the federal government about $25 billion annually in foregone revenue. That sounds like it benefits homeowners enormously. In reality, nearly 75% of that benefit flows to households earning over $100,000 per year. Households under $50,000 collected essentially nothing from it.
The Consumer Financial Protection Bureau (CFPB) has resources that walk you through what itemizing actually involves and what counts toward your Schedule A total. Worth reading before you assume you’ll benefit.
My honest take: the mortgage interest deduction is a tax benefit that mostly helps upper-income buyers in expensive housing markets. If that’s not you, building your budget around it is a mistake I’ve seen sink people before.
If you’re unsure where you stand, a HUD-approved housing counselor can help you think through this without trying to sell you a loan. That’s a free resource and genuinely underused.
Sources
- IRS Publication 936: Official IRS guidance on home mortgage interest deduction rules, limits, and eligibility (updated annually).
- Tax Policy Center: Research on the distributional effects of the mortgage interest deduction, including income-by-bracket breakdowns.
- Congressional Budget Office: Federal revenue cost estimates for major tax expenditures including the mortgage interest deduction.
- IRS Statistics of Income: Data on itemized deduction usage rates and taxpayer filing patterns.
- Consumer Financial Protection Bureau, Owning a Home: Plain-language homebuyer resources including deduction and tax guidance.
Photo: Vitaly Gariev via Pexels
This article is for educational purposes only and does not constitute financial or mortgage advice. Mortgage rates change daily and vary by lender, loan type, credit profile, and property details. Consult a HUD-approved housing counselor (find one at hud.gov) or licensed mortgage professional for guidance specific to your financial situation.
Recommended Resources
Disclosure: As an Amazon Associate, we earn a small commission from qualifying purchases at no extra cost to you. We only recommend products that genuinely support the topics covered in this article.
- First-Time Home Buyer: The Complete Playbook (~$18), The #1 Amazon bestseller in homebuying, covers down payment strategies, mortgage pre-approval, and avoiding rookie mistakes.
- 100 Questions Every First-Time Home Buyer Should Ask (~$17), Nearly a million copies sold, covers every question to ask your lender, agent, and inspector before signing anything.
