If you're headed off to a familiar U.S. destination on short notice, with few or no reservations, you probably don't need travel insurance. But insurance may be worth a thought if you're buying a cruise or tour package that requires hefty prepayments and carries heavy penalties for late cancellations.
This doesn't mean insurance is a great bargain--analysts at Consumers Reports have called travel insurance "the most overpriced of all travel services"--but it can sometimes supply protection and peace of mind.
Trip cancellation/interruption insurance typically covers your losses if a family medical crisis or certain other emergencies force you to abandon or abbreviate a trip. Emergency medical coverage covers emergency transport or medical care or both. Insurance companies frequently offer "bundled" coverage that includes both types, along with a few other provisions, such as coverage if your bags are lost.
For cancellation/interruption insurance, prevailing premium rates are $5.50 to $6.50 per $100 of trip cost. Thus it typically costs $110 to $130 to cover a $2,000 trip. A package of "bundled" coverage usually costs more.
Some insurers, like Travel Guard International, don't offer separate cancellation/interruption coverage. Others, such as Travelex Insurance Services, sell no more than $1,000 in stand-alone cancellation/interruption coverage, but will cover costlier trips if you also buy their bundled package of other coverages.
A few more details to remember:
* For many years, most travel insurers would not cover recurrences of preexisting medical conditions. But since a burst of marketplace jostling about four years ago, most major companies will cover most preexisting conditions if you buy the coverage within seven or 14 days of making your first payment on the trip. (That way, the insurance company gets your money sooner, perhaps even six months ahead of your departure date.)
* Trip cancellation/interruption and bundled policies often include protection if your travel supplier (the tour operator, for instance) defaults. But in many cases, you only get that protection if you buy the policy straight from the insurance company, and not through the tour operator.
* At least one insurer, C.S.A. Travel Protection, has set premiums lower for younger travelers, higher for older ones. Cutoff ages are typically 55 and 70, and the oldest travelers can end up paying twice as much as the youngest for coverage of the same trip. (Consumer Reports named C.S.A. the best value in the field for travelers 70 and under.) Most other major insurers say they don't consider travelers' ages.
Though consumers can buy travel insurance through travel agents, cruise lines and tour operators, some authorities suggest that consumers request brochures from insurers themselves and buy direct. A sampling follows:
Access America, telephone (800) 284-8300 (Access America also administrates the American Express Vacation Protection Plan, which is not limited to American Express cardholders; tel.  756-2639).
Carefree Travel Insurance, tel. (800) 323-3149; offered by the Berkely Group, based on Long Island, N.Y.
C.S.A. Travel Protection, tel. (800) 348-9505; based in San Diego.
Globalcare Insurance Services, tel. (800) 821-2488; based in Lynnfield, Mass.
International S.O.S. Assistance, tel. (800) 523-8662. Medical coverage.
Travelex Insurance Services, tel. (800) 228-9792; based in Omaha, Neb.
Travel Guard International, tel. (800) 826-1300; based in Stevens Point, Wis.
Travel Insurance Services, tel. (800) 937-1387; based in Walnut Creek, Calif.
Travel Insured International/The Travelers, tel. (800) 243-3174; based in East Hartford, Conn.
Travelsafe, tel. (800) 523-8020; sold through Chester Perfetto Agency of Wyomissing, Pa.
Tripguard Plus, tel. (800) 423-3632; sold through M.H. Ross Co. in Northridge, Calif.
Worldwide Assistance Services, tel. (800) 821-2828; based in Washington, D.C. Medical coverage.
Wallach & Co., tel. (800) 237-6615; based in Middleburg, Va. The company specializes in medical coverage, including HealthCare Abroad and HealthCare Global policies, but can include cancellation/interruption coverage.