I am 65, still working, and have Medicare and my job's health plan. Which one pays first?

Health insuranceWho paysChecked Nov 6, 2026

From K.Actuary, founded by Sangmin Kwon, ASA · sources checked 2026-11-06 · Source: CMS · Medicare and Other Health Benefits: Your Guide to Who Pays First (Pub. 02179) · PDF text · PDF page 6 View original ↗

In short

It depends on how big the employer is.
If the employer has 20 or more employees, the work plan generally pays first and Medicare second.
If the employer has fewer than 20 employees, Medicare pays first.

What this means

This is from Medicare's own guide. It covers people who are 65 or older and have a plan through their own or a spouse's job right now.

Generally, if the employer has 20 or more employees, the group health plan pays first and Medicare pays second [1]. If the group health plan did not pay the whole bill, your provider should send the rest of the bill to Medicare [2].

If the employer has fewer than 20 employees, and is not part of a multi-employer group where one company has 20 or more, the rule changes [3]. Then Medicare pays first and the group health plan pays second [4].

If your work plan is second, you may need to sign up for Medicare Part B before it will pay [5]. We do not have your plan or your employer's size. Don't know yet which case you are in. Ask your plan.

Your next step

Ask your employer's benefits office how many employees the company has and whether your plan pays first or second for you. The guide sets no deadline for this.

Check it yourself

Open the Medicare guide above and read the section for people who are 65 or older and still working. Then ask your plan, in writing, if it pays first or second for you, and keep the answer.

Where this comes from (5)

[1] CMS · Medicare and Other Health Benefits: Your Guide to Who Pays First (Pub. 02179) · PDF text · PDF page 6 · checked 2026-11-06
Generally, your (or your spouse’s) group health plan pays first and Medicare pays second.
[2] CMS · Medicare and Other Health Benefits: Your Guide to Who Pays First (Pub. 02179) · PDF text · PDF page 6 · checked 2026-11-06
If the group health plan didn’t pay your entire bill, your provider should send the bill to Medicare for secondary payment.
[3] CMS · Medicare and Other Health Benefits: Your Guide to Who Pays First (Pub. 02179) · PDF text · PDF page 6 · checked 2026-11-06
If your (or your spouse’s) employer has fewer than 20 employees (and isn’t part of a multi-employer group where at least one company has 20 or more employees)
[4] CMS · Medicare and Other Health Benefits: Your Guide to Who Pays First (Pub. 02179) · PDF text · PDF page 6 · checked 2026-11-06
Medicare pays first and the group health plan pays second.
[5] CMS · Medicare and Other Health Benefits: Your Guide to Who Pays First (Pub. 02179) · PDF text · PDF page 4 · checked 2026-11-06
If your group health plan or retiree coverage is the secondary payer, you may need to sign up for Medicare Part B before they’ll pay.

How we found this

We matched your question to 5 official sources, quoted the exact lines, and re-checked each quote against its source on 2026-11-06.

What we don’t know yet

Your own plan or notice may say something different. If your letter cites another rule, send it and we will look again.

Every answer is checked against the official rule it quotes.

Information only — not legal advice. Your plan, insurer or agency decides.

This answer quotes the official sources listed above, with the date we checked them. Your own policy, notice and state rules control. We are not your lawyer or your insurer. We don’t file, argue or negotiate claims for you — you send any letter or form yourself.

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