(MONEY Magazine) – In today's travel maze of bankruptcies and nonrefundable deals, trip insurance may sound like a safety net. But don't leap: travel coverage is typically sold in ''bundles,'' which may include features you don't need. What's more, policies can add a steep 8% or so to a trip's cost and often provide only secondary coverage. That is, they reimburse you merely for the amounts you can't collect from other sources, such as your health carrier. Therefore, Mary Ann Gillis of the Insurance Information Institute says you should check your existing protection before buying trip insurance. Health and homeowners policies, for example, usually cover you for illness and lost or stolen belongings when you're on the road. Does trip insurance ever pay off? Sometimes -- though not often: -- Baggage. Benefits for lost or stolen luggage tend to be skimpy ($1,000 or less), and cameras, jewelry and currency top a long list of excluded items. Furthermore, airlines automatically cover each passenger's bags for up to $1,250 total on domestic flights and about $625 a bag on international hauls. Bottom line: consider baggage insurance only if your homeowners policy lacks an ''off premises'' clause. -- Medical. Generally, this duplicates standard major-medical insurance. But if you rely on benefits such as Medicare, which does not cover treatment outside the U.S., find a carrier that sells just travel medical. The tab? Roughly $40 for 14 days -- with a maximum of $15,000 worth of treatment. -- Life and accident. Also hawked at airports for $10 a round trip, this insurance, says Jim Hunt of the National Insurance Consumer Organization, ''is a poor buy that plays on people's fear of flying.'' Credit-card issuers often throw in life insurance when you charge an air ticket. All in all, your current coverage is probably enough. -- Trip cancellation. Today's new hot seller, cancellation insurance comes in handy if you feel compelled to bail out of a prepaid or nonrefundable trip because of, say, illness or a terrorist scare. Most policies reimburse you for up to $1,000. Several firms also sell policies separately for about $5.50 per $100 worth of coverage, sometimes including vendor default and bankruptcy.

Before buying any travel coverage, quiz your agent and choose plans underwritten by major insurance companies, such as: Carefree (800-323-3149), which is underwritten by Hartford Insurance, has its headquarters in Mineola, N.Y. Tele-Trip (800-228-9792), affiliated with Mutual of Omaha, is in Omaha. Travel Guard International (800-782-5151), based in Stevens Point, Wis., is underwritten by TransAmerica. Travel Insurance Pak (800-243-3174), which is underwritten by The Travelers, is located in Hartford.