NEW YORK (Tribune Media Services) - IRS publications don't list any tax deductions for summer vacations. But there are several ways the tax code can help subsidize some pleasurable travel this summer.

Business travelers can mix some vacation into a tax-deductible business trip -- and even bring the family along. Others may be able to write off a trip connected to a professional association convention, job search, continuing-education seminar or volunteer charitable work.

If you have some sort of business trip scheduled this summer, such as a professional association convention or trade show, you might consider adding a little vacation to the itinerary.

When a trip includes both business and pleasure, you can generally deduct hotel and meal costs only for the days you're conducting business. But so long as the primary purpose of your trip is business, you can deduct 100 percent of the cost of transportation.

For example, if you fly to Hawaii to attend a five-day business convention and stay an extra few days to relax on the beach and sightsee, you can deduct lodging and meals for your five days of business. Plus, you'd be able to deduct your entire roundtrip airfare since the primary purpose of your trip is business. (Foreign travel is subject to more complicated rules and sometimes requires transportation costs to be prorated.)

There are even a couple of situations in which you can deduct living costs for some of your vacation days. If you have business to conduct on a Friday and a Monday, you can usually deduct your living expenses for the weekend in between -- even if you spend all Saturday and Sunday in pleasurable pursuit.

If your business ends on a Friday, you may still be able to deduct some weekend lodging and meal expenses if your layover is intended to take advantage of lower airfares for staying a Saturday night. The IRS ruled in a case involving a corporate travel policy that the extra living expenses could be deducted provided they didn't exceed the airfare savings.

With school out for the summer, business travelers are likely to get extra pressure from family members to tag along on business trips -- especially if the destination is a resort area.

Taking family members on a business trip needn't diminish your business write-offs for the trip. When it comes to deducting the cost of your hotel room, for instance, you don't have to apportion the cost between yourself and other members of your family. Rather you're allowed to deduct what you would have paid if you traveled alone. In other words, you can deduct the single-occupancy rate for the room, which is often only slightly less than the double-occupancy rate you'll actually pay for your family.

Similarly, you can deduct transportation expenses based on what it would have cost you to travel alone. So if you use your own car or rent one, you can generally deduct the full cost.

Travel to an out-of-town job interview can be deducted if you're looking for a new job in the same line of work.

But don't think you can turn your weeklong family vacation to Disney World into a deductible trip simply by squeezing into the itinerary a job interview in the Orlando area.

How much time you spend on business compared to the time spent vacationing is important in determining the primary purpose of the trip. So the IRS would consider the primary purpose of your trip to Disney World to be vacation because so little time was spent on business. And that means you wouldn't be able to write off any of your airfare to Orlando or any other trip costs, except perhaps for the cab ride from your hotel to the job interview.

If you perform out-of-town services for a charitable group, you may be able to deduct your travel costs. For instance, if you're a scoutmaster and take a Boy Scout troop on a camping trip this summer, your travel costs are eligible for a charitable deduction.

But so-called "volunteer vacation" travel programs sponsored by environmental and research organizations are difficult to write off. The IRS bars deductions if the trip has any "significant element of personal pleasure, recreation or vacation."

Travel to an out-of-town convention of a charitable or religious organization can be written off as a charitable contribution if you're a chosen representative to the convention. For example, if you're selected by your church to be a delegate to a national religious convention, you can deduct the cost of transportation, lodging and meals. If you're not an official delegate, but just attending the convention on your own, none of the costs are deductible.

Professional education seminars offer another deductible travel opportunity for doctors, lawyers and other professionals. Travel costs for continuing-education seminars, which are often held in popular resort areas, are deductible if the education is needed to maintain or upgrade skills in your current job and the education is the main purpose of your trip.