What Is Coordination of Benefits?

When you need care and are on two different health insurance plans, your insurers will coordinate your benefits (COB). This helps you get maximum coverage when you need it.

If you’re covered by two different health plans, your provider may file the claim with both plans. The health insurers will decide which plan covers certain expenses on the claim. This is called Coordination of Benefits. If there are times when your primary plan doesn’t cover the whole claim, the secondary plan may cover them all or pay a certain amount. It depends on the COB rules.

How It Works

Coordination of benefits may be needed if:

• You are on your employer's health plan and on the plan your spouse has with their employer.
• You buy your own health plan, but you are also on your spouse's group plan.
• You and your spouse have individual policies and are listed as dependents on both.
• You have dependent children covered under both your and your spouse's health plan.
• A custody agreement requires one parent to cover the children, but both parents choose to include them on their coverage.

If you have Medicare and another plan, coordination of benefits is always used. Medicare may be the primary or secondary payor. It depends on the Medicare coordination of benefits. Let your insurer know up front if you have Medicare. It will save you and your doctor time when filing claims.

Why Coordination of Benefits?

Coordination of benefits helps:

• Avoid duplicate payments so the two plans don’t pay more than the total amount of the claim
• Make sure the proper payments are made by each plan
• Reduce the cost of insurance premiums

You may get a form in the mail, an email or a call from your insurer to set up the coordination of benefits. You may also want to document any other coverage  you have when your plan renews each year.

Even if you don’t have other coverage, you'll need to let your insurer know. Sometimes claims are held until coordination of benefits is confirmed. A provider won’t be paid until primary and secondary coverage is confirmed.

Want To Know More?

If you have more than one health plan, check out the section of your benefit materials called Coordination of Benefits to learn how it works.

For more information, call the customer service number listed on your health plan's member ID card.

Source: Coordination of Benefits,  ehealthinsurance.com; Coordination of Benefits,  Centers for Medicare and Medicaid Services, 2023; How Medicare works with other insurance,  medicare.gov

Originally published November 23, 2020; Revised 2021, 2024