How Does the IRS Define a Second Home? Tax Rules

The IRS does not use one universal definition of a second home for every tax rule, but it generally means a home you own and use in addition to your main home. Depending on the rule, a home can include a house, condominium, cooperative, mobile home, house trailer, or boat with sleeping, cooking, and toilet facilities.

Your main home is generally the place where you ordinarily live most of the time, while a second home might be a vacation house or a condominium you use on weekends. Owning more than one property does not automatically mean that every additional property receives the same tax treatment, so you need to consider how you use each one.

For the mortgage interest deduction, a qualified home can generally include your main home and one second home, subject to the applicable debt limits and other requirements. If you rent out your second home, it generally qualifies as a residence for this purpose only if your personal use exceeds the greater of 14 days or 10% of the days you rent it at a fair rental price.

For example, if you rent a property at a fair price for 100 days during the year, you generally need more than 14 days of personal use to meet that test. Personal-use days can include certain days when family members or other people use the property, so keep a calendar and records of rental payments and expenses.

Using a second home for work does not by itself make the property your main home or automatically qualify you for a home office deduction. If you are eligible to claim that deduction, the workspace generally must meet IRS requirements for regular and exclusive business use, along with the applicable business-use tests.

For practical ideas, our home office setup guide covers workspace planning for different spaces. You can also explore our Your Ultimate Home Office Guide, a digital download with a printable eBook and workspace setup planner.

When you split your time between properties, the home where you spend the most time is generally your main home for federal tax purposes. Other facts can matter too, including where you work, where your family lives, and the address you use for important records.

We recommend keeping records of your time and use at each property, particularly if you rent one out or plan to claim a deduction. Our team suggests reviewing the specific IRS rules that apply to your situation, because the definition and treatment of a home can differ depending on the tax question.