A medical bill arriving in an envelope.

Getting sick or injured is especially miserable when you're on vacation. What may be even worse is getting hit with a big medical bill when you arrive home from your ruined getaway.

If you have health insurance and have a medical crisis that requires a trip to an emergency room while you're traveling in the U.S., “your plan should cover you regardless of location,” says Sean Malia, a senior director at eHealth, an online site for buying health insurance.

But if you have a relatively minor problem—say, you sprained your ankle or suspect your child has strep throat—how much of your bill is covered can depend on where you seek care and the type of insurance you have, says Cathryn Donaldson, director of communications at America’s Health Insurance Plans, a trade association for insurance companies.

Your insurer may treat your out-of-town healthcare as an out-of-network claim. As a result, you could be on the hook for a larger portion of the cost or the whole bill.

How to Minimize Vacation Healthcare Costs

As vacation season heats up, add these tasks to your pre-trip to-do list to protect yourself from a surprise medical bill.

1. Pack your medical information. Make sure you have an up-to-date insurance card in your wallet. Put your healthcare providers’ contact info in your phone in case you need a referral. Also, take along a list of all your medications and dosages.

More on preventing surprise medical bills

2. Don't forget your meds. If your current supply of prescription drugs won’t last for the duration of your trip, ask your insurer for a “vacation override” so that you can get an early refill. If you run out while you’re away, check with your insurance company in addition to calling your doctor. Most insurers contract with national retail drugstore chains that will provide refills once your doctor contacts them.

3. Know what your insurer covers. Ask your insurer ahead of time how it defines an emergency and what will be covered if you need treatment away from home. See whether your insurer has a mobile app that can help you find ERs, urgent care centers, pharmacies, and doctors that the company covers along your route or request a list from your insurer.

4. Give your doctor a heads-up. If you have a chronic condition, such as asthma or diabetes, contact your physician before you travel to ask for a referral to other doctors who could treat you at your destination, if necessary.

5. Take advantage of telemedicine. Most insurers offer telehealth services, which allow you to have a video consultation with a doctor via your smartphone, computer, or tablet. It usually costs less than seeing a doctor in person, and some teledocs can prescribe short-term medication.

Editor's Note: This article also appeared in the July 2018 issue of Consumer Reports magazine.