Couple on vacation © Corbis

You've got that resort wardrobe packed, the itinerary nailed down and an insatiable desire for drinks with umbrellas. And then it happens: the unexpected. A summons for jury duty, your best friend gets ill, you have a sudden family emergency or you have to forego a trip because you lose your job. Missing a trip is just one reason to purchase travel insurance.

There are some travel mishaps that just can't be avoided and unexpected costs that can't be recovered. But travel insurance can be a security blanket worth packing on your next vacation.

Here are five solid reasons to consider buying travel insurance for your next big vacation:

1. Missing a trip. If you can't take that long-planned-for vacation, there's a lot to lose. All of that nonrefundable money for plane tickets, hotel reservations and island tours is at risk. Travel insurance can reimburse your expenses incurred for situations that cause a missed trip, but be aware of deductibles, exclusions and restrictions.

2. An interrupted trip. With the proper coverage, you also can receive a refund for expenses incurred if your journey is interrupted. Such circumstances could include a cruise ship with mechanical failure at sea, a natural disaster or weather emergency – or something as simple as a missed flight connection overseas.

3. A canceled trip. Perhaps your trip is canceled due to reasons not related to you. Travel insurance can cover that, too. Events that might trigger a refund can include regional terror threats, weather-related cancellations and transportation labor strikes.

4. Lost baggage. One of the most common inconveniences during a trip is having your baggage lost or misrouted and delayed. Travel protection can be purchased for this, too. But first, check your existing homeowners or renters insurance coverage. Many times these policies will cover personal belongings that are lost, stolen or damaged while on vacation. Again, deductibles and limitations often apply. Expensive purchases made while traveling may require special travel insurance, so check with your agent for policy limits and exclusions.

5. Medical emergencies. Your existing health insurance may cover you to some degree while traveling, but complications can include medical care outside of your provider network or the exclusion of coverage overseas. Some health care providers in other countries also require immediate payment. Travel insurance may be able to fill the gaps in your health insurance coverage in the event of an accident or medical emergency. However, be aware that some policies may limit coverage for pre-existing conditions and older travelers.

Before purchasing travel insurance

Check to see if the seller is licensed by the state in which the seller is located. If the firm is not licensed, it may not be selling insurance at all – and may be carefully hiding that fact. You want to be sure the seller is financially sound and able to pay claims. Companies that aren't licensed aren't held to the same standard as properly credentialed agents and may not adhere to consumer protection laws and regulations.

Verify if traveling companions and family members are covered under a travel policy you're considering. Coverage may vary depending if the other parties are staying in the same hotel, cabin or room, and if they take the same or separate flight.

And if you're embarking on an adventure vacation, determine if the travel policy you are considering covers skydiving, scuba diving or that BASE jump you're planning!

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