US Mortgage Interest Tax Deduction Calculator
Calculate exactly how much you save in federal income tax on your mortgage interest. Based on your actual marginal rate — free, instant, no signup.
Current loan principal
From your mortgage statement
Needed to calculate your marginal tax rate — the deduction saves you more the higher your bracket.
How the US Mortgage Interest Deduction Works
The mortgage interest deduction lets US homeowners deduct the interest paid on qualified home loans from their federal taxable income. The deduction is only valuable if you itemize deductions on Schedule A — rather than taking the standard deduction ($14,600 single / $29,200 married filing jointly in 2024).
Because the 2017 Tax Cuts and Jobs Act nearly doubled the standard deduction, only about 10–12% of taxpayers now itemize. The deduction is most beneficial for high earners with large mortgages or multiple deductible expenses.
Your saving depends directly on your marginal tax rate: a 37% taxpayer saves $37 in federal tax for every $100 of interest paid. A 22% taxpayer saves only $22 for the same $100.
Loan Limit and Rules (2024)
The deduction applies to interest on qualified residence loans up to $750,000 ($375,000 married filing separately). Loans originated before December 15, 2017 have a higher cap of $1,000,000.
- Applies to your primary and one secondary home — not investment properties
- Covers mortgage interest and sometimes mortgage insurance premiums
- Home equity loan interest is deductible only if used to buy, build, or substantially improve the home
- Points paid at closing may be deductible in full the year paid or amortized over the loan
Standard vs Itemized Deduction — Should You Itemize?
To benefit from the mortgage interest deduction, your total itemized deductions must exceed your standard deduction. In 2024, the standard deduction is $14,600 (single) or $29,200 (married filing jointly).
Add up: mortgage interest + state/local taxes (SALT, capped at $10,000) + charitable contributions + other itemized deductions. If this total exceeds your standard deduction, itemizing makes sense.
Example: Single filer, $600k mortgage at 6.5% → $39,000 interest. Plus $10,000 SALT = $49,000 total. This well exceeds the $14,600 standard deduction — so itemizing saves significant tax.
Frequently Asked Questions
Do I get the deduction automatically?
No — you must file Schedule A (Form 1040) to itemize. Your lender sends Form 1098 each year showing the mortgage interest paid.
Does the deduction apply to state income taxes too?
Many states follow federal rules and allow a similar deduction. Some states (like California) have their own limits. The calculator above shows only federal savings.
Is BeastyTax free?
Yes, completely free — no account, no hidden costs.