You may think you’re covered if you have health insurance, but Consumer Reports wants you to think again especially if you’re going out-of-network.

According to Consumer Reports, one of the most common causes of medical sticker shock is by going out-of-network.

Two services – HealthCareBlueBook.com and FairHealthConsumer.org — let you search the cost of medical services by zip code and sometimes you can use this information to negotiate with the non-network provider you want to use.

You can get more information on your medical costs here.