Which describes the standard process for payer assignment in coordination of benefits (COB)?

• A. Determine primary payer first, then bill secondary payer for remaining balance if applicable.
• B. Bill all payers in parallel to minimize delays.
• C. Always bill the facility first regardless of payer type.
• D. Assume patient is primary if multiple payers are present.

Answer: (A)

In coordination of benefits, the essential idea is to establish the payment order when a patient has more than one health plan. The standard process is to determine which plan is primary and bill that payer first. After the primary payer processes the claim, you bill the secondary payer for the remaining balance, if applicable. This sequence ensures that benefits are applied correctly and avoid overpaying or underpaying the patient.

Context helps: COB rules decide which plan pays first (primary) and which pays second (secondary) based on factors like employment status, plan type, and sometimes the dependent’s birthday under the birthday rule. The secondary payer may cover part or all of what remains after the primary payment, up to the secondary plan’s terms, and any remaining amount can then be billed to the patient if not covered by either plan. If the primary payer denies or reduces payment, the secondary plan may still step in according to its own rules.

Billing all payers in parallel can create confusion and timing issues, and paying the facility first regardless of payer type ignores the established order of benefits. It’s also not correct to assume the patient is always primary when multiple payers exist.