Coordination of Benefits (COB)

Also called: COB

In plain English

The process of determining which insurance plan pays first when you're covered by two or more health plans. The primary plan pays first, then the secondary plan may cover some or all of the remaining costs.

Real-world example

You have insurance through your employer and are also covered under your spouse's plan. Your employer plan is primary and pays first. Your spouse's plan is secondary and may pick up remaining costs like deductibles or coinsurance.

Why this matters for your bill

If you have dual coverage and coordination of benefits isn't set up correctly, claims can be denied or delayed. Make sure both insurance companies know about each other and which is primary vs. secondary.

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