IRS Form 1098: The Complete Guide to Your Mortgage Interest Statement
Most homeowners toss their Form 1098 into a pile of tax documents without really understanding what it means for their bottom line. That's a costly mistake—for many homeowners, mortgage interest is the single largest itemized deduction available, potentially saving thousands of dollars each tax season.
This guide breaks down everything you need to know about IRS Form 1098: what it is, what every box means, how to use it on your tax return, and what's changed in 2026 that makes this form more valuable than ever.
What Is IRS Form 1098?
Form 1098, officially called the Mortgage Interest Statement, is a tax form that your mortgage lender sends you each January. It reports how much mortgage interest, mortgage insurance premiums (MIP), and points you paid during the previous tax year.
The form serves two purposes:
- For you (the borrower): It provides the information you need to claim a mortgage interest deduction on your federal tax return.
- For the lender: It documents the interest they received, which they must report as income to the IRS.
If you paid $600 or more in mortgage interest in a calendar year, your lender is legally required to send you a Form 1098 by January 31.
Who Receives Form 1098?
You'll receive Form 1098 if:
- You have a mortgage on your primary or secondary home
- You paid $600 or more in interest during the year
- Your lender is a financial institution, credit union, savings and loan, or any business that regularly receives mortgage interest
You will not receive Form 1098 if you have a mortgage with a private lender (like a family member) or if the property is a rental or investment property—though interest on those loans may still be deductible under different rules.
Understanding Every Box on Form 1098
The form has 11 boxes, but a few matter more than others for your tax return:
Box 1: Mortgage Interest Received
This is the most important box. It shows the total mortgage interest you paid during the year. This is the primary figure you'll transfer to your tax return to claim the mortgage interest deduction.
Box 2: Outstanding Mortgage Principal
Your outstanding loan balance as of January 1 of the reporting year (or the origination date if the mortgage was new). The IRS uses this to verify whether your deduction falls within the allowed debt limits.
Box 3: Mortgage Origination Date
The date your mortgage loan began. This date matters for determining which deduction limit applies to your loan (more on this below).
Box 4: Refund of Overpaid Interest
If your lender refunded any interest you overpaid in a prior year, that amount appears here. This is technically taxable income if you deducted the original payment.
Box 5: Mortgage Insurance Premiums (MIP)
If you pay private mortgage insurance (PMI) or FHA mortgage insurance premiums, those payments appear in Box 5. For tax year 2026, mortgage insurance premiums remain deductible as mortgage interest on Schedule A.
Box 6: Points Paid on Purchase of Principal Residence
Points (also called loan origination fees or discount points) you paid when you first bought your home. These are generally fully deductible in the year you paid them if they meet IRS requirements, though points on refinanced mortgages must typically be deducted over the life of the loan.
Boxes 7–9: Property Information
These boxes identify the property address, whether you have multiple properties securing the mortgage, and whether the property is the borrower's principal residence.
Box 10: Other Information
Lenders can use this box to provide additional information relevant to your deduction.
Box 11: Mortgage Acquisition Date
For mortgages acquired after 2016, this box shows when the lender acquired the mortgage. It's primarily used for institutional recordkeeping.
The Mortgage Interest Deduction: What You Need to Know
Deduction Limits
Not all mortgage interest is fully deductible. The Tax Cuts and Jobs Act (TCJA) of 2017 established the current limits:
| Loan Origin Date | Deductible Debt Limit | MFS Limit |
|---|---|---|
| After December 15, 2017 | $750,000 | $375,000 |
| On or before December 15, 2017 | $1,000,000 | $500,000 |
If your mortgage balance exceeds these limits, you can only deduct a proportional share of the interest. For example, if you have a $1 million loan originated in 2022, you can deduct 75% of the interest reported in Box 1.
Qualified Homes
The deduction applies to:
- Your primary residence (the home where you live most of the year)
- One second home (vacation home, cabin, boat with sleeping/cooking/bathroom facilities)
You cannot deduct mortgage interest on a third property, investment property, or rental property using Schedule A (rental property interest goes on Schedule E instead).
Itemizing vs. Taking the Standard Deduction
To benefit from Form 1098, you must itemize deductions on Schedule A. For tax year 2026, the standard deduction is:
- $16,100 for single filers
- $32,200 for married filing jointly
- $24,150 for heads of household
If your total itemized deductions—mortgage interest, property taxes, charitable donations, and other eligible expenses—exceed your standard deduction, itemizing makes sense. If they don't, you're better off taking the standard deduction, even if you paid significant mortgage interest.
Big News for 2026: The SALT Cap Change
Here's something that makes Form 1098 especially worth paying attention to this year: the state and local tax (SALT) deduction cap has dramatically increased for 2026.
From 2018 through 2025, the SALT deduction was capped at $10,000. This cap prevented millions of homeowners in high-tax states like California, New York, and New Jersey from itemizing because their property taxes alone often exceeded the standard deduction threshold only when combined with mortgage interest—yet the $10,000 SALT cap left them short.
For 2026, the SALT cap has risen to approximately $40,000 (adjusted for inflation). This change means many homeowners who previously had no reason to itemize now may benefit significantly from doing so—and Form 1098 is central to that calculation.
Example: A homeowner in New Jersey who pays $18,000 in property taxes and $22,000 in mortgage interest now has $40,000 in potential deductions from just those two categories, well above the $32,200 married filing jointly standard deduction.
How to Use Form 1098 on Your Tax Return
Step 1: Collect Your Form 1098
Your lender must send Form 1098 by January 31. You may receive it by mail or electronically through your lender's online portal. If you have multiple mortgages (including a home equity loan), you'll receive a separate Form 1098 for each.
Step 2: Decide Whether to Itemize
Add up all potential itemized deductions:
- Mortgage interest (Box 1 of Form 1098)
- Points (Box 6, if applicable)
- Mortgage insurance premiums (Box 5, if applicable)
- State and local taxes (property taxes + income or sales taxes, up to the SALT cap)
- Charitable contributions
- Other eligible expenses
If the total exceeds your standard deduction, proceed with itemizing.
Step 3: Complete Schedule A
Transfer the deductible amounts to Schedule A of Form 1040:
- Line 8a: Deductible home mortgage interest reported on Form 1098 (Box 1)
- Line 8b: Home mortgage interest not reported on Form 1098 (for private lenders)
- Line 8c: Points not reported on Form 1098
- Line 8d: Mortgage insurance premiums (Box 5)
Step 4: Check the Debt Limit
If your outstanding principal (Box 2) exceeds $750,000 (or $1,000,000 for pre-2018 loans), you'll need to calculate your deductible percentage and report it accordingly on the worksheet provided in IRS Publication 936.
Common Mistakes to Avoid
Assuming all interest is deductible: If your loan exceeds the debt limits, you need to calculate the deductible portion—don't just enter Box 1 without checking.
Forgetting about points on a purchase: Points paid when buying a home (Box 6) are often fully deductible in the year paid, but many taxpayers miss this.
Missing the rental property distinction: If you rent out your home for more than 14 days per year, different rules apply, and you may need to allocate interest between Schedule A and Schedule E.
Not keeping the form: The IRS recommends retaining Form 1098 for at least three years in case of an audit. Since mortgage interest deductions are relatively large and commonly scrutinized, holding onto documentation is especially important.
Ignoring refinance situations: When you refinance, you receive a new Form 1098. Points paid on a refinance are generally deducted over the life of the loan, not all at once—unlike purchase points.
What to Do If You Don't Receive Form 1098
If you paid more than $600 in mortgage interest but haven't received Form 1098 by mid-February:
- Contact your lender's customer service department
- Log into your lender's online portal—many now provide digital copies
- Check whether your mortgage servicer changed during the year (you may receive a form from the new servicer, or two forms from both)
You can still claim the mortgage interest deduction even without a Form 1098, but you'll need documentation of your payments and will report the interest on a separate line of Schedule A (Line 8b) along with the lender's name, address, and taxpayer identification number.
Form 1098 Variants
"Form 1098" is actually a family of related forms:
- Form 1098-E: Student Loan Interest Statement (reports student loan interest paid)
- Form 1098-T: Tuition Statement (used to claim education tax credits)
- Form 1098-C: Contributions of Motor Vehicles, Boats, and Airplanes (for charitable donations)
- Form 1098-F: Fines, Penalties, and Other Amounts (not related to homeownership)
When someone refers to "Form 1098" in the context of mortgages, they almost always mean the original, unnumbered mortgage interest version.
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