How Medicare works with employer insurance depends on the size of the employer. For employers with 20+ employees: employer insurance is primary, Medicare is secondary. For employers with fewer than 20 employees: Medicare is primary, employer insurance is secondary. You should enroll in Medicare Part B when it is primary.
Key Points
- 20+ employees: employer insurance is primary, Medicare is secondary
- Fewer than 20 employees: Medicare is primary, employer insurance is secondary
- Enroll in Medicare Part B when it is primary to avoid late enrollment penalties
- Coordinate benefits with your employer's HR department
- An independent agent can help you understand Medicare coordination with employer insurance