Here are the five most important things you need to know about your health insurance coverage before you go on vacation.

1). Your current policy may not cover healthcare costs abroad. First and foremost, find out if your existing health insurance policy covers medical care while you’re away from home. Whether you are traveling within the United States or to another country, your insurance policy may only cover some – or none – of your healthcare costs while you’re away. Policies will vary among private providers, but Medicare and Medicaid only provide medical coverage within the United States.

2) You should purchase supplemental insurance with medical evacuation coverage. If your existing health insurance policy doesn’t cover travel, you can purchase supplemental health insurance and receive temporary coverage for the duration of your international trip. Sometimes you can find less expensive options through your current health insurance company, so be sure to ask them first. Otherwise, you can purchase your supplemental coverage from any travel medical insurance provider up to 24 hours before you leave.

• TIP: When you buy supplemental travel health insurance, make sure you have evacuation coverage to help cover any costs associated with transporting you to medical care. This is especially important if you are travelling to a remote location because it typically covers air rescue and emergency transportation home.

3) Be prepared to pay for your healthcare costs upfront. Travel health insurance works differently than your healthcare coverage at home. Within the United States, you usually pay little to no money at the time of your treatment. Internationally, however, you will probably have to pay for your medical costs out-of-pocket and upfront, and then be reimbursed when you return home.

• TIP: Make sure you save any receipts and documentation associated with your international treatment! These will be important when you submit a claim with your insurance company back home.

4) Know whether your travel health insurance is considered primary or secondary. While this doesn’t necessarily impact the quality or level of coverage, it does affect how you file a claim when you return home.

If your travel health insurance policy is primary, you only need to file a claim with the company who issued that policy. (This process remains the same if your travel insurance is considered secondary and you have no other international healthcare coverage.)

However, if you have “secondary” travel health insurance as well as some international coverage through your primary health insurance policy, you must first file a claim with your primary insurance company for the portion of the cost covered under their policy. You will then need to file another claim with your secondary insurance provider to cover the remaining costs.

5) Adventurous activities require additional coverage. Many travel health insurance policies do not cover medical costs associated with adventurous activities, such as rock climbing, scuba diving, or hang gliding. If you plan on partaking in any adventure sports while you’re away, make sure to read the fine print of your policy and purchase additional coverage as necessary.