Coordination of benefits

What does Coordination of benefits mean on a medical bill?

Coordination of benefits is how two plans decide which one pays first when you are covered twice — through a spouse, a parent, or a job plus another policy. The first plan processes the claim, then the second one looks at what is left. It shows up in bill reviews for a boring reason: plans send a letter asking whether you have other coverage, and until you answer, claims sit denied. People throw the letter away, then get a bill months later for care that was always covered.

What should I watch out for with Coordination of benefits?

• A denial asking about other coverage — call your plan and answer, since claims stall until you do
• A child covered by two parents' plans — ask which plan is primary before paying anything
• A bill after both plans processed — compare both EOBs before deciding what is actually left