When your spouse's employer plan covers you
If your spouse works for an employer with 20+ employees and you're covered under their plan, you can generally delay Medicare Part B without penalty. The same rules apply as if it were your own employer coverage — the 20-employee threshold is what matters.
Common scenarios
You turn 65, spouse still works
If your spouse's employer has 20+ employees and you're on their plan, you can delay Part B. Enroll in free Part A if you don't have an HSA. When your spouse retires, use your 8-month SEP.
You retire, spouse keeps working
You may be able to stay on your spouse's employer plan as a dependent. If their employer has 20+ employees, this coverage counts for delaying Part B. Verify with their HR department.
Both turning 65 at different times
Each spouse makes independent Medicare decisions. The first to turn 65 evaluates based on the working spouse's employer coverage. The second spouse does the same when their time comes.
Spouse's employer has fewer than 20
Medicare is primary. Both spouses should enroll in Medicare at 65 regardless of the employer plan.
Divorce and Medicare
If you're divorced but were married for at least 10 years, you may qualify for Medicare based on your ex-spouse's work record. This can be important if you don't have 40 quarters of work history yourself. Contact Social Security at 1-800-772-1213 to check eligibility.
Colorado community property note
Colorado is not a community property state, so each spouse's Medicare eligibility is determined independently based on their own (or their current/former spouse's) work history.