Medicare Secondary Payer (MSP) situations
Look up common Medicare Secondary Payer situations and which coverage generally pays before Medicare.
Updated
Medicare Secondary Payer (MSP) rules decide when another payer must pay before Medicare. Search common MSP situations to see which coverage generally pays first and the condition that triggers it. The rules, employer-size thresholds, and coordination periods are set by federal law and CMS and can change, and the correct answer for a specific claim depends on the beneficiary's exact circumstances — confirm the current rule with CMS and the applicable payer.
8 situations shown
| Situation | Generally pays first | Condition and notes |
|---|---|---|
Working aged — age 65 or older with a group health plan through current employment | Group health plan (Medicare pays second) | Generally applies when coverage is through the current employment of the beneficiary or spouse and the employer has 20 or more employees; where the employer is smaller, Medicare generally pays first. Confirm the current threshold with CMS. |
Disability — under 65 and Medicare-entitled by disability, with a large group health plan | Large group health plan (Medicare pays second) | Generally applies when coverage is through the current employment of the beneficiary or a family member and the employer has 100 or more employees; otherwise Medicare generally pays first. |
End-stage renal disease (ESRD) during the coordination period | Group health plan (Medicare pays second) | During a statutory coordination period (currently up to 30 months) the group health plan pays first regardless of employer size or how coverage is obtained; after the period, Medicare generally pays first. Confirm the current coordination period with CMS. |
Workers' compensation — care for a work-related injury or illness | Workers' compensation | Workers' compensation pays first for treatment of the work-related condition. Medicare does not pay for services that workers' compensation is responsible for; a Workers' Compensation Medicare Set-Aside may apply. |
No-fault or automobile insurance — care for an accident | No-fault or automobile insurance | Pays first for services related to the accident, up to policy limits. Medicare may make a conditional payment and later seek repayment from the settlement or insurer. |
Liability insurance — care for an injury another party is liable for | Liability insurance | Pays first for accident-related care. While a liability claim is pending, Medicare may pay conditionally and recover from any settlement, judgment, or award. |
Federal Black Lung Program — care for black lung disease | Federal Black Lung Program | Pays first for services related to black lung disease. Medicare does not pay for care the program covers; unrelated care follows normal Medicare rules. |
Department of Veterans Affairs (VA) authorized care | VA, for VA-authorized services | Medicare and VA benefits do not coordinate as primary and secondary; the beneficiary chooses which to use for a given service. VA-authorized care is billed to the VA, and Medicare generally does not pay for it. |
Check the controlling source
This lookup summarizes general MSP rules for orientation; it is not a coverage determination for a specific claim. Employer-size thresholds and coordination periods are statutory and may change. Use the CMS Medicare Secondary Payer manual and CMS guidance as the controlling sources.
Source and currency
CMS Medicare Secondary Payer situation types · Updated Thresholds and coordination periods are statutory; confirm current values with CMS · Reviewed July 18, 2026
CMS — Medicare Secondary Payer Manual (IOM Pub. 100-05) (opens in a new tab)
Related Knowledge
- Medicare Secondary Payer (MSP) billing
How MSP is determined and billed.
- Medicare Secondary Payer (MSP)
- Coordination of benefits (COB)