Coverage end date: COBRA election notice mailed:
| Clock | Rule | Your deadline | Done ☐ |
|---|---|---|---|
| Marketplace special enrollment | 60 days from losing job-based coverage to pick a plan; coverage starts the first of the month after you select | ☐ | |
| COBRA election | 60 days from the later of coverage end or the election notice mailing | ☐ | |
| COBRA first payment | 45 days after you elect, covering all months back to the loss date | ☐ | |
| Spouse's employer plan | 30 days from your loss date for your spouse to request enrollment | ☐ | |
| Day-40 checkpoint | calendar alarm before either 60-day window expires | ☐ |
Also running: the employer has 44 days from the qualifying event to mail the COBRA notice; COBRA ongoing payments get a 30-day grace each month, no bills required, termination if missed; Medicaid has no window (apply any day); open enrollment runs November 1 through mid-January. Parent plan under 26: same special enrollment windows, 30 days typical on employer plans.
| Door | Start rule | Your start date |
|---|---|---|
| Marketplace | selected in a month, starts the first of the next month (select April 10, starts May 1; the hole is what the COBRA backstop covers) | |
| COBRA | retroactive to your loss date when elected, at full-freight premiums for the plugged months | |
| Spouse plan | prospective in most plans, first of the month after the form clears; get the effective date in writing (the enrollment gap nobody owns) |
| If you... | Then... |
|---|---|
| Elect COBRA | The mid-year marketplace switch closes until open enrollment or COBRA runs out; dropping it early does not open a new window; exhausting it naturally opens one, 60 days |
| Lose Medicaid or CHIP | 90 days rather than 60 |
| Marry, have a child, or move counties | Each opens its own window |
| Miss everything | Open enrollment, November into January, reopens it all |
Upload the proof the day you apply rather than waiting for the request; processing the proof is what makes the enrollment stick, and denials are usually missing-paperwork problems.
The windows do not pause for negotiations with HR, a slow election notice, or a busy launch month. The 60-day marketplace window measured from your loss date closes even if the COBRA notice arrives on day 50.