Health insurers participating on the health insurance marketplaces must provide consumers shopping for coverage with a directory of their in-network providers. However, these lists can quickly become out of date and may not contain the most current and accurate list of participating providers. Furthermore, you can incur significantly higher out-of-pocket costs if you obtain services outside your plan’s network. Therefore, if you have a provider that you want to keep seeing, you should contact the provider and confirm that they participate in the plans you’re considering. (45 C.F.R. § 156.230(b)).