Mortgage interest can lower your tax refund, but only if you itemize deductions

Mortgage interest does not automatically increase your tax refund. Instead, it reduces the income you pay taxes on, which can lower the amount of tax you owe — and therefore change the size of your refund. The key word is "can." Whether mortgage interest actually affects your refund depends on whether you choose to itemize deductions or take the standard deduction on your tax return.

Here is the basic idea: if you own a home with a mortgage, you can deduct the interest you paid that year from your taxable income. Deducting means subtracting. A smaller taxable income means you owe less tax. If you overpaid tax during the year through paycheck withholding, a smaller tax bill means a larger refund. But this only works if itemizing deductions saves you more money than the standard deduction would.

Key Takeaways

  • Mortgage interest reduces your taxable income only if you itemize deductions instead of taking the standard deduction.
  • The standard deduction for 2024 is $14,600 for single filers and $29,200 for married couples filing jointly, and most people benefit from taking it instead of itemizing.
  • You can only deduct mortgage interest on loans up to $750,000 of the home's purchase price, and only if you itemize.
  • To know whether itemizing helps your refund, add up all your deductions (mortgage interest, property taxes, charitable donations, medical expenses) and compare that total to the standard deduction.

The standard deduction versus itemizing

When you file taxes, you must choose one path: take the standard deduction or itemize deductions. You cannot do both. The standard deduction is a flat amount the IRS lets you subtract from your income with no questions asked. For the 2024 tax year, the standard deduction is $14,600 for single filers and $29,200 for married couples filing jointly. These amounts change each year.

Itemizing means listing out specific expenses you paid during the year — mortgage interest, property taxes, charitable donations, medical expenses — and adding them up. If your total itemized deductions exceed the standard deduction, itemizing saves you more money. If they do not, the standard deduction is the better choice.

Most people benefit from the standard deduction because it is already quite large. You would need to own a home with a high mortgage balance, live in a state with high property taxes, or have other large deductible expenses to make itemizing worthwhile.

How much mortgage interest can you deduct

If you do itemize, you can deduct the interest you paid on a mortgage used to buy, build, or improve your home. The IRS limits this deduction to interest on loans up to $750,000 of the home's purchase price. If your mortgage is larger than that, you can only deduct interest on the first $750,000.

You cannot deduct mortgage interest on a home equity line of credit or a cash-out refinance unless the money was used to improve the home itself. You also cannot deduct interest on a second mortgage or investment property mortgage unless specific conditions are met.

The mortgage company sends you a Form 1098 each January showing how much interest you paid the previous year. This is the number you use when itemizing.

When itemizing actually increases your refund

Itemizing increases your refund only if two things are both true: first, your itemized deductions (including mortgage interest) add up to more than the standard deduction, and second, you overpaid taxes during the year through paycheck withholding or estimated tax payments.

Here is an example. Suppose you are married filing jointly, your itemized deductions total $35,000, and your standard deduction would be $29,200. By itemizing, you reduce your taxable income by an extra $5,800 compared to taking the standard deduction. If your tax rate is 22 percent, that saves you about $1,276 in taxes. If you overpaid your taxes by $4,000 during the year, your refund would be $4,000 minus $1,276 in taxes owed, or $2,724. Without the mortgage interest deduction, your refund would have been $4,000 minus $2,552 in taxes owed, or $1,448. The deduction increased your refund by $1,276.

But if you did not overpay taxes during the year, itemizing would not change your refund — it would just reduce the amount you owe when you file.

Why most homeowners do not benefit from mortgage interest deductions

The Tax Cuts and Jobs Act of 2017 nearly doubled the standard deduction. Because of this change, the number of people who benefit from itemizing dropped sharply. Today, roughly 90 percent of tax filers use the standard deduction.

To benefit from itemizing, you typically need a mortgage of at least $400,000 to $500,000 in a state with moderate property taxes, or a smaller mortgage in a high-tax state like California, New York, or New Jersey. Even then, you need other deductible expenses — charitable donations, medical costs, or state and local taxes — to push your total above the standard deduction.

If you have a smaller mortgage or live in a low-tax state, the standard deduction almost certainly saves you more money than itemizing would.

How to figure out if mortgage interest affects your refund

To know whether mortgage interest will change your refund, gather these numbers: the mortgage interest shown on your Form 1098, your state and local property taxes, any charitable donations you made, and any significant medical or dental expenses. Add these up. If the total is higher than the standard deduction for your filing status, itemizing may help your refund. If the total is lower, the standard deduction is your better choice.

You can also use the IRS Interactive Tax Assistant tool on IRS.gov to compare the two options, or work through the calculation with tax software when you file. Many tax software programs will automatically calculate both scenarios and show you which one saves more money.

If you are close to the standard deduction threshold, remember that you can only deduct mortgage interest on loans up to $750,000 of the home's purchase price, and only if you itemize. Mortgage interest on amounts above that limit cannot be deducted.

What happens if you refinance your mortgage

Refinancing does not change how mortgage interest deductions work. You still deduct the interest you actually paid during the year, regardless of when you refinanced. If you refinanced partway through the year, you deduct interest paid to the old lender before the refinance and interest paid to the new lender after it.

One thing to watch: if you refinanced for more than the original loan amount (a cash-out refinance), you can only deduct interest on the portion used to buy, build, or improve the home. Interest on the cash-out portion is not deductible unless you used that money for home improvements.

Frequently Asked Questions

Does paying off my mortgage early reduce my tax refund?

Yes, it can. Paying off your mortgage means you pay less interest that year, so you have a smaller mortgage interest deduction to claim. If you were itemizing, this reduces your itemized deductions total. However, most people do not itemize anyway, so paying off your mortgage would not affect their refund at all.

Can I deduct mortgage interest if I do not itemize?

No. Mortgage interest is only deductible if you itemize deductions. If you take the standard deduction, you cannot claim mortgage interest separately. This is why most homeowners do not benefit from the mortgage interest deduction — they save more money by taking the standard deduction.

What if I paid points to lower my mortgage interest rate?

Points paid to reduce your interest rate can sometimes be deducted, but the rules are complex and depend on whether you paid them upfront or rolled them into the loan. If you paid points, your Form 1098 should show any deductible amount. If you are unsure, check the form or speak with a tax preparer.

Does mortgage interest affect my refund if I am self-employed?

The mortgage interest deduction works the same way for self-employed people as for employees — it only helps if you itemize deductions. However, self-employed people may also deduct a home office deduction if they use part of their home exclusively for business, which is a separate calculation.

Will I get a bigger refund if I have a larger mortgage?

Not necessarily. A larger mortgage means more interest to deduct, but only if you itemize and only if your total deductions exceed the standard deduction. For most people, the standard deduction is large enough that a bigger mortgage does not change their refund at all.