Mortgage Interest Deduction: What Homeowners Need to Know
How to deduct mortgage interest on your primary and secondary home — loan limits, qualifying debt, and how to claim it.
Quick Answer
Yes, mortgage interest may be deductible if you itemize deductions on Schedule A. You can deduct interest on up to $750,000 of qualifying mortgage debt ($375,000 if married filing separately) for loans taken out after December 15, 2017. Older loans have a higher $1 million limit. Your lender will send a Form 1098 each year showing the interest you paid.
What Mortgage Interest May Qualify?
The mortgage interest deduction applies to interest paid on loans used to buy, build, or substantially improve your home. It is one of the largest itemized deductions available to homeowners and often makes itemizing worthwhile even when other deductions are modest.
Potentially deductible mortgage interest includes:
- Primary home mortgage interest — Your main residence
- Second home mortgage interest — A vacation home or second property you don’t rent out
- Home equity loan interest — If the loan was used to buy, build, or improve your home
- Home equity line of credit (HELOC) interest — Same requirement: funds used for the home
- Mortgage points paid at closing — May be fully deductible in the year paid
- Late payment fees — Charges for late mortgage payments are deductible as interest
Mortgage interest works alongside property taxes, home office expenses, and homeowners insurance to build your total itemized home deductions.
Loan Limits That Apply
Current Mortgage Debt Limits (Tax Cuts and Jobs Act)
Loans after Dec. 15, 2017: Deductible on up to $750,000 of mortgage debt
Married filing separately: $375,000 limit per person
Loans before Dec. 16, 2017: Grandfathered at the higher $1,000,000 limit
Home equity debt: Only deductible if used to buy, build, or improve the home — not for personal expenses
Example Calculation:
Mortgage balance: $600,000 (under the $750,000 limit)
Interest rate: 6.5%
Annual mortgage interest paid: ~$38,400
Property taxes: $8,000
Total Schedule A home deductions: $46,400
Standard deduction (2024, single): $14,600
Benefit of itemizing: $46,400 vs. $14,600 — itemizing clearly wins here
How to Claim Mortgage Interest
- Receive Form 1098 from your lender by late January (shows total interest paid)
- Confirm loan amount is within deductible limits
- Add mortgage interest to other itemized deductions (property taxes, charitable giving, etc.)
- Compare total itemized deductions to your standard deduction
- If itemizing is larger, report mortgage interest on Schedule A, Line 8a or 8b
- Enter total itemized deductions on Form 1040
What Mortgage Expenses Don’t Qualify?
- Principal payments — Only interest is deductible, not the principal portion of your payment
- Homeowners insurance — Not deductible for a personal residence (only for rental/home office use)
- Home equity interest used for personal expenses — If HELOC funds paid for a car or vacation, that interest doesn’t qualify
- Mortgage on a third home — Only primary and one secondary residence qualify
- Reverse mortgage interest — Not deductible until the loan is paid off
Tips for Maximizing Your Mortgage Interest Deduction
Always compare itemizing vs. standard deduction — The 2024 standard deduction is $14,600 (single) and $29,200 (married filing jointly). If your total itemized deductions including mortgage interest don’t exceed these amounts, the standard deduction is better. Run the numbers every year.
Stack with property taxes — Mortgage interest and property taxes are the two biggest home deductions and go on the same Schedule A. Together they often make itemizing worthwhile even when other deductions are small.
Deduct points in the right year — Points paid to get your original mortgage are typically fully deductible in the year paid. Refinance points must be deducted over the life of the loan. Understand which situation applies to you.
Track home equity loan use carefully — If you have a HELOC or home equity loan, keep records proving the funds were used for home improvements. This is the key requirement for the interest to remain deductible and is worth documenting clearly alongside other home improvement records.
Consider the home office deduction — If you work from home, the business-use percentage of your mortgage interest may also flow through the home office deduction on Schedule C, potentially producing additional tax benefit beyond Schedule A.
Common Questions About Mortgage Interest
Can I deduct mortgage interest on a rental property?
Yes, but rental property mortgage interest is reported on Schedule E, not Schedule A. It’s deducted as a rental expense rather than an itemized deduction, and the $750,000 loan limit doesn’t apply to rental properties.
What if I refinanced my mortgage?
Interest on a refinanced mortgage is generally deductible up to the loan limit that applies. If you took cash out during refinancing, only the portion used to improve your home qualifies — cash used for personal purposes does not. Points paid on a refinance are deducted over the loan term, not all in year one.
Do I need Form 1098 to claim the deduction?
Form 1098 from your lender makes it easy, but you can claim the deduction without it if you have records of interest actually paid. If you paid interest to a private lender rather than a financial institution, they may not issue a 1098 — keep your own records in that case.
Can both spouses deduct mortgage interest if filing separately?
Yes, but the $750,000 limit is split — each spouse can deduct interest on up to $375,000 of mortgage debt when filing separately. You must divide the deduction between you, which can be complex. Filing jointly is often simpler and more beneficial.