A second home is a residence you own in addition to your primary home and use mainly for personal purposes — vacations, family visits, or an eventual retirement spot — rather than as a rental business. The IRS and mortgage lenders each apply their own tests to decide whether a property qualifies, and the classification affects your mortgage rate, your down payment, which deductions you can claim, and what you owe when you sell. If you are asking what is a second home in a way that has real tax and financing consequences, the answer sits at the intersection of how you use the property and how often anyone else does.
What Kind of Property Qualifies
Under 26 U.S.C. § 280A, a dwelling unit includes a house, apartment, condominium, mobile home, boat, or similar property, along with any structures attached to it.1Office of the Law Revision Counsel. 26 USC 280A – Disallowance of Certain Expenses in Connection With Business Use of Home, Rental of Vacation Homes, Etc. Houseboats and recreational vehicles can qualify, provided the property serves a residential purpose rather than operating as a hotel or similar commercial lodging.
The IRS adds a practical floor: a dwelling unit must have basic living accommodations, meaning sleeping space, a toilet, and cooking facilities.2Internal Revenue Service. Publication 527 (2025), Residential Rental Property A rustic cabin missing a working toilet or any way to cook may not meet that standard. Confirm those features exist before you rely on second-home tax benefits.
The Personal-Use Test
To keep a property classified as a residence for tax purposes, you must use it personally for more than the greater of 14 days per year or 10 percent of the days it is rented at fair market price.1Office of the Law Revision Counsel. 26 USC 280A – Disallowance of Certain Expenses in Connection With Business Use of Home, Rental of Vacation Homes, Etc. Rent it out for 200 days and you need at least 21 personal-use days. Rent it out for 100 days and the 14-day floor applies, because 14 exceeds 10 percent of 100.3Internal Revenue Service. Topic No. 415, Renting Residential and Vacation Property
The IRS counts a day as personal use if you, a co-owner, or a family member of either uses the property, even when you are not there. Family for this purpose covers spouses, siblings, parents, grandparents, children, and grandchildren. A day someone stays at below-market rent counts. So does a day used under a home-swap arrangement, and so does donating the property’s use to a charity fundraiser.2Internal Revenue Service. Publication 527 (2025), Residential Rental Property
Drop below the personal-use threshold and the IRS treats the home as a rental property, which changes your allowable deductions, your reporting obligations, and can pull you into depreciation rules. Consistent personal use through the year is the simplest way to preserve second-home treatment.
The 14-Day Rental Rule
Rent your second home for fewer than 15 days in a year and you do not report that income at all. Section 280A specifically excludes it from gross income.1Office of the Law Revision Counsel. 26 USC 280A – Disallowance of Certain Expenses in Connection With Business Use of Home, Rental of Vacation Homes, Etc. You also cannot deduct any expenses tied to that short rental period. Money in, nothing to report, nothing to write off.
Cross the 14-day line and everything changes. All rental income becomes reportable, and you must allocate shared expenses like mortgage interest and utilities between personal and rental use based on rental days over total use days.2Internal Revenue Service. Publication 527 (2025), Residential Rental Property When the property still qualifies as your residence, rental deductions generally cannot exceed rental income for the year, and any excess carries forward. Tracking who occupies the property on every day of the year is essential once you rent at all.
How Lenders Classify a Second Home
Mortgage lenders apply their own rules on top of the IRS definitions. To finance a property as a second home rather than an investment, lenders typically require that you maintain exclusive control of the property and that it not be subject to a timeshare or mandatory rental agreement.4Fannie Mae. B2-1.1-01, Occupancy Types The property should function as a personal retreat, not a revenue operation.
Distance From Your Primary Home
Most lenders expect a meaningful distance between the two homes, commonly at least 50 to 100 miles. A “vacation home” three miles from your main house looks more like a rental than a getaway. Properties in recognized resort, mountain, or coastal areas may face less scrutiny on distance because the vacation purpose is obvious. No single federal rule sets an exact mileage, so requirements vary by lender.
Down Payment and Credit
Second-home mortgages generally require a larger down payment than primary-residence loans. A minimum of 10 to 15 percent down is typical for a conventional loan on a single-unit second home, against as little as 3 percent for a primary home. Most lenders look for a credit score in the mid-600s or higher and a debt-to-income ratio at or below 45 percent, with the best rates going to borrowers above 700 and with strong reserves.5Fannie Mae. B3-6-02, Debt-to-Income Ratios
Why the Label Affects Your Rate
If a lender decides the property is an investment rather than a second home, you pay a higher rate and put more money down. Investment loans carry more risk for lenders, so the pricing is steeper. Documentation of the distance from your main home, the property’s location in a vacation area, and your intent to use it personally helps secure the lower second-home rate.
Mortgage Interest, Property Tax, and SALT
A second home qualifies for the same mortgage interest deduction as your primary residence. You can deduct interest on the first $750,000 of combined mortgage debt across both homes ($375,000 if married filing separately). Mortgages that originated on or before December 15, 2017 keep the legacy $1 million limit ($500,000 if married filing separately).6Internal Revenue Service. Publication 936 (2025), Home Mortgage Interest Deduction You claim the deduction on Schedule A of Form 1040, which means itemizing rather than taking the standard deduction.
The One Big Beautiful Bill Act, signed in July 2025, made the $750,000 limit permanent; it had been set to expire after 2025. The same law raised the state and local tax deduction cap to $40,000 ($20,000 if married filing separately), up from $10,000. The SALT cap phases down for taxpayers with modified adjusted gross income above $500,000 ($250,000 if married filing separately), and it is indexed for inflation starting in 2026.7Internal Revenue Service. How to Update Withholding to Account for Tax Law Changes for 2025 Property taxes and mortgage interest are usually the two biggest deductions tied to a second home, so both changes matter.
What Changes When You Sell
Selling a second home triggers capital gains tax, and the rules are tighter than for a primary residence. The Section 121 exclusion, which shields up to $250,000 in profit ($500,000 for married couples filing jointly), applies only to a property you owned and used as your principal residence for at least two of the five years before the sale.8Office of the Law Revision Counsel. 26 USC 121 – Exclusion of Gain From Sale of Principal Residence A property used only as a second home fails that test.
Without the exclusion, your profit is taxed at long-term capital gains rates if you held the property for more than a year. For most taxpayers the rate is 15 percent, ranging from 0 percent at lower incomes to 20 percent at higher incomes. If you rented the property and claimed depreciation, the portion of gain attributable to that depreciation is taxed at up to 25 percent.
Moving In Before You Sell
One planning move is to make the second home your principal residence for at least two years and then sell. Meeting the ownership and use tests — owning and living in the home as your main home for two of the five years before the sale — qualifies you for the Section 121 exclusion.9Internal Revenue Service. Topic No. 701, Sale of Your Home It requires a genuine change in where you live, not a paper reclassification, and you cannot have claimed the exclusion on another home sale within the previous two years.
1031 Exchanges Do Not Apply
A 1031 like-kind exchange, which defers capital gains by reinvesting sale proceeds into another property, is available only for property held for business or investment use. A second home used mainly for personal enjoyment does not qualify.10Internal Revenue Service. Like-Kind Exchanges Under IRC Section 1031 Owners who have rented extensively and can show the property was held as an investment may have a case, but a home that doubles as a personal vacation retreat will draw IRS scrutiny.
Ongoing Costs You May Not Expect
Most states offer a homestead exemption that reduces property taxes on a primary residence, and second homes almost never qualify. Exemption amounts vary widely by jurisdiction, from a few hundred dollars in savings to reductions of tens of thousands in assessed value, so losing it on a second property can meaningfully raise your annual tax bill. Check with the local assessor where the second home sits.
Homeowners insurance also tends to run higher. Insurers view a property that sits empty for stretches as a greater risk for undetected water damage, break-ins, and weather problems. Expect premiums roughly 10 to 30 percent above a comparable primary residence, with the exact difference tied to location, condition, and how often the home is occupied. Some insurers require a vacancy rider or a specialized policy if the home is unoccupied for more than 30 consecutive days.