HomeMath
Blog

The Mortgage Interest Deduction

The mortgage interest deduction lets homeowners reduce taxable income by the interest they pay on a qualifying mortgage. But the 2017 tax law changed who actually benefits.

How it works

You can deduct interest on up to $750,000 of mortgage debt for a primary or secondary home. The deduction is only valuable if you itemize deductions instead of taking the standard deduction.

The catch

The standard deduction is large enough now ($14,600 single, $29,200 married in 2024) that most homeowners do not itemize. If your mortgage interest plus other deductions is under that, the deduction does nothing for you.

Who still benefits

Big mortgages in high-tax states, combined with the state and local tax (SALT) deduction, are the cases where itemizing usually wins. Early in a loan, when interest is front-loaded, is when the deduction matters most.

The bottom line

Do not buy a house for the tax deduction. Treat it as a small bonus at most. Focus on the actual cost — our calculator shows total interest, which is the number that really matters.

See your real payment

Reading is step one. Step two is running your own numbers — taxes, insurance, PMI and all.

Open the mortgage calculator