| Date | What happens |
|---|---|
| Oct 15, 2026 | Medicare open enrollment starts (Medicare Advantage and Part D changes) |
| Nov 1, 2026 | HealthCare.gov open enrollment starts for 2027 plans (a few state exchanges open earlier) |
| Dec 7, 2026 | Medicare open enrollment ends |
| Dec 15, 2026 | Last day on HealthCare.gov to pick a plan that starts Jan 1, 2027 |
| Jan 1, 2027 | Coverage starts if you enrolled by Dec 15 and paid the first premium |
| Jan 15, 2027 | HealthCare.gov open enrollment ends (coverage starts Feb 1) |
| Varies | State-run exchanges (for example California and New Jersey run to Jan 31) and employer plans set their own dates |
Before your window closes
- Work plan: compare the HSA plan and the PPO with your real premiums: HSA vs PPO calculator.
- Marketplace: enhanced tax credits ended after 2025, so check your 2027 credit: 2027 tax credit table and marketplace vs employer calculator.
- Leaving a job: COBRA vs marketplace calculator.
- HSA: plan your deposits with the 2027 HSA limits and the per-paycheck calculator.
- Use the open enrollment checklist.
Sources: HealthCare.gov dates and deadlines; Medicare.gov. Checked October 14, 2026. State exchange dates can differ; check your state.
General education, not insurance, tax or legal advice. Figures from IRS and HHS publications; confirm with your plan documents.