What Qualifies as a Second Home for Tax Purposes?

A property qualifies as a second home for tax purposes when it contains sleeping space, cooking facilities, and a toilet, and you use it for personal purposes enough days each year that the IRS does not treat it as a rental. That personal use minimum is the greater of 14 days or 10 percent of the days the property is rented at fair market value. Meeting the threshold lets you deduct mortgage interest on the property, subject to a combined $750,000 mortgage debt cap across your primary and second homes, and lets you deduct property taxes within the state and local tax cap.

What Structures Count

Federal law defines a “dwelling unit” broadly. It includes houses, apartments, condominiums, mobile homes, boats, and similar properties, along with any structures attached to them.¹ For mortgage interest purposes, the IRS requires that the unit have sleeping, cooking, and bathroom facilities.² Houseboats, RVs, and mobile homes can all qualify as long as they have a bed, a stove or cooking area, and a toilet.

Cooperative apartments qualify too. If you own stock in a cooperative housing corporation and have the right to live in a unit, mortgage debt secured by that stock is treated the same as debt secured by a traditional home.³

Property used as a hotel, motel, or inn does not count. Undeveloped land by itself does not qualify either.

The Personal Use Threshold

A property counts as a second home only if you use it personally for more than the greater of 14 days or 10 percent of the total days it is rented at a fair market rate during the year.⁴ Rent it out for 200 days and you need at least 21 days of personal use, because 10 percent of 200 is larger than 14. Fall below that line and the IRS reclassifies the property as a rental, which changes which deductions apply and how you report income.

Personal use is not limited to days you personally spend at the property. Any day a family member stays there counts toward your total, even if they pay nothing. Under the tax code, family includes your spouse, siblings (including half-siblings), parents, grandparents, children, and grandchildren.⁵ Any day someone else uses the property at below-market rent also counts as personal use, and so does any house-swap arrangement where someone stays in your place while you stay in theirs.⁴

Days That Do Not Count

A day spent doing repairs or maintenance work at the property, meaning upkeep like fixing a leaky faucet or repainting a wall rather than improvements, does not count as personal use, even if family members are there enjoying the property at the same time.⁶ You must work on repairs substantially full time that day for the exception to apply.

If You Never Rent It Out

The personal use threshold only matters if you rent the property. A home you own purely for occasional personal use qualifies automatically as a second home, and you do not have to visit it at all during the year.²

The 14-Day Tax-Free Rental Rule

Rent your second home for fewer than 15 days during the year and the rental income is completely excluded from your gross income. You do not report it on your tax return.⁷ The trade-off is that you cannot deduct any expenses tied to the rental use, including advertising and cleaning fees.¹ The 14-day limit is strict. Rent for 15 days or more and all of the rental income becomes taxable.

Deducting Mortgage Interest

You can deduct mortgage interest on your second home the same way you deduct it on your primary residence, but the total mortgage debt across both properties is capped at $750,000, or $375,000 if you are married filing separately.⁸ The limit was introduced in 2018 under the Tax Cuts and Jobs Act and made permanent by the One Big Beautiful Bill Act. The prior $1 million limit no longer applies to any new mortgages taken out after December 15, 2017.

You must itemize on Schedule A to claim the deduction. Only one property beyond your primary residence qualifies, and you choose which one each year. Married couples filing separately are treated as one taxpayer for this purpose, so together the two of you can claim a primary residence and one second home unless you both agree in writing to a different arrangement.³

Property Taxes and the SALT Cap

Property taxes on a second home are deductible if you itemize, but they fall inside the state and local tax cap. That cap applies to the combined total of state income taxes (or sales taxes), local taxes, and real property taxes across all your properties. For 2026, the cap is approximately $40,000, or $20,000 if married filing separately, with a slight upward adjustment each year through 2029.⁹ The cap phases down for taxpayers with modified adjusted gross income above roughly $500,000, eventually reaching a floor of $10,000.

Property taxes on your primary residence, your second home, and your state income taxes all share this one cap. If your state income taxes alone approach the limit, the property taxes on a second home may add little or nothing to your deduction.

When the Property Gets Treated as a Rental

If your personal use falls below the threshold, the property is a rental rather than a second home in the eyes of the IRS. Rental income and expenses get reported on Schedule E instead of qualifying for the homeowner deductions on Schedule A. The shift also triggers passive activity loss rules, which can limit your ability to use property losses to offset wages or other non-rental income.¹⁰

When you use a property partly for personal enjoyment and partly as a rental, you must allocate expenses between the two uses. The IRS method divides expenses based on the ratio of rental days to total days the property was used, personal plus rental. Some courts have applied a different formula for mortgage interest and property taxes, dividing rental days by the 365 days in the year rather than just the days the property was occupied. The court method allocates less interest and taxes to the rental side, which can leave more room for deducting maintenance and depreciation against rental income.

Reporting a property as a second home when it actually functions as a rental can trigger an accuracy-related penalty of 20 percent of the underpaid tax, rising to 40 percent in cases involving gross valuation misstatements.¹¹

Selling a Second Home

Selling a second home does not qualify you for the capital gains exclusion available on a primary residence. The Section 121 exclusion of up to $250,000 for single filers or $500,000 for married couples filing jointly applies only to property you have owned and used as your principal residence for at least two of the five years before the sale.¹² A second home you never lived in as your primary residence does not qualify.

Profit from the sale is taxed as a capital gain. If you owned the property for more than a year, long-term capital gains rates apply. For 2026 those rates are:

0 percent on taxable income up to $49,450 (single) or $98,900 (married filing jointly)
15 percent on taxable income from $49,451 to $545,500 (single) or $98,901 to $613,700 (joint)
20 percent on taxable income above $545,500 (single) or $613,700 (joint)

High earners may also owe the 3.8 percent net investment income tax on top of the capital gains rate. This surtax applies to gains from selling investment real estate, including second homes, when your modified adjusted gross income exceeds $200,000 (single) or $250,000 (married filing jointly). These thresholds are not adjusted for inflation.¹³

Moving Into a Second Home

Move into your second home and make it your primary residence, and you can eventually qualify for the Section 121 exclusion, but not on the full gain. The portion of your profit attributable to “nonqualified use” periods, meaning the years the property was not your principal residence, does not qualify for the exclusion.¹² The allocation is based on the ratio of nonqualified use time to total ownership. Own a property for 10 years, use it as a second home for 6, and then live there as your primary residence for 4, and roughly 60 percent of the gain would be taxable while 40 percent could qualify for the exclusion.

One exception favors the seller. Any period after the last day you used the property as your principal residence does not count as nonqualified use. Temporary absences of up to two years for job relocations, health reasons, or unforeseen circumstances are also excluded from the nonqualified use calculation.¹²

Records to Keep

Detailed records are what defend your second-home classification if the IRS questions it. The single most important document is a calendar or log tracking every day the property was used for personal purposes versus rented. Record the names of anyone who stays there, since that helps verify whether family use or below-market arrangements triggered personal use days. Rental agreements with third-party tenants should include dates, rental amount, and tenant name.

Keep utility bills, maintenance receipts, and repair invoices that corroborate the dates in your use log. If you claim that certain days were spent on full-time repairs rather than personal use, receipts for materials and a written description of the work strengthen that position.¹⁴ If you rent to friends or relatives at a discount, evidence of fair market rent in your area matters. Comparable listings, rental market reports, or prior-year rental agreements for the same property can show the IRS that your rate was reasonable. Keep all property-related records for at least three years after filing the return for that tax year, or longer if the property involves ongoing depreciation or you plan to sell.¹⁵

1
Office of the Law Revision Counsel. 26 U.S. Code 280A – Disallowance of Certain Expenses in Connection With Business Use of Home, Rental of Vacation Homes, Etc.
2
Internal Revenue Service. Publication 936, Home Mortgage Interest Deduction
3
Legal Information Institute. 26 U.S. Code 163(h)(4)(A) – Definition of Qualified Residence
4
Office of the Law Revision Counsel. 26 USC 280A – Disallowance of Certain Expenses in Connection With Business Use of Home, Rental of Vacation Homes, Etc. – Section: Use as Residence
5
Office of the Law Revision Counsel. 26 U.S. Code 267 – Losses, Expenses, and Interest With Respect to Transactions Between Related Taxpayers
6
Internal Revenue Service. Publication 527, Residential Rental Property
7
Internal Revenue Service. Topic No. 415, Renting Residential and Vacation Property
8
Office of the Law Revision Counsel. 26 U.S. Code 163 – Interest
9
Internal Revenue Service. Topic No. 503, Deductible Taxes
10
Internal Revenue Service. Topic No. 414, Rental Income and Expenses
11
Office of the Law Revision Counsel. 26 USC 6662 – Imposition of Accuracy-Related Penalty on Underpayments
12
Office of the Law Revision Counsel. 26 USC 121 – Exclusion of Gain From Sale of Principal Residence
13
Internal Revenue Service. Questions and Answers on the Net Investment Income Tax
14
Internal Revenue Service. Tips on Rental Real Estate Income, Deductions and Recordkeeping
15
Internal Revenue Service. How Long Should I Keep Records?