Getty Images August 1, 2008 Whether you use your vacation getaway every weekend or just a few times a year, you may want to rent it out occasionally to offset some of your expenses. That's fine, as long as you don't set off any alarms with the Internal Revenue Service.1. If you rent out your house for 14 days or fewer during the year, you don't have to report the rental income on your tax return. And there's no limit to how much you can charge. The house is considered a personal residence so you deduct mortgage interest and property taxes just as you do for your primary home. 2. If you rent out your house for more than 14 days, you become a landlord in the eyes of the IRS. That means you have to report your rental income. But it also means you can deduct rental expenses. It can get complicated because you need to allocate costs between the time the property is used for personal purposes and the time it is rented. 3. If you use the place for more than 14 days or more than 10% of the number of days it is rented -- whichever is greater -- it is considered a personal residence. You can deduct rental expenses up to the level of rental income. But you can't deduct losses. Advertisement 4. The definition of "personal use" days is fairly broad. They may include any days you or a family member use the house (even if the family member is paying rent). Personal days also include days on which you have donated use of the house -- say, to a charity auction -- or have rented it out for less than fair market value. 5. If you limit your personal use to 14 days or 10% of the time the vacation home is rented, it is considered a business. You can deduct expenses and, depending on your income, you may be able to deduct up to $25,000 in losses each year. That's why many vacation homeowners hold down leisure use and spend lots of time "maintaining" the property; fix-up days don't count as personal use.