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Sources and Method
What is sourced, how current it is, and what we left out.
How we handle facts
- Every number and rule on this site comes from Medicare.gov, CMS, KFF, KFF Health News, the NAIC or a state insurance department or SHIP program, and the page says which.
- Where a source gives a window or a date, we use its wording. Where sources did not state a detail, we say "not stated" or leave it out. We do not estimate premiums, plan counts or savings.
- The state lookup lists the states that the sources identify. A state shown as "none found" means only that the sources reviewed did not list a rule there.
How current
- 2026 Medicare amounts: CMS fact sheet and Medicare.gov costs page (2026).
- Medigap guaranteed issue and birthday rules: KFF (published October 13, 2026) and the NAIC chart (as of May 11, 2026), supplemented by Virginia's State Corporation Commission and Indiana's SHIP (July 2026).
- Last review: October 2026.
Not covered
Plan-specific details, premiums by company, Medicare Advantage plan quality, drug formularies, Medicaid, and rules for people under 65 beyond brief mentions. Rules change; new state laws can take effect any time.
Sources
- Medicare.gov: Compare Original Medicare & Medicare Advantage
- Medicare.gov: Medicare costs (2026)
- CMS: 2026 Medicare Parts A & B Premiums and Deductibles
- Medicare.gov: Special Enrollment Periods
- Medicare.gov: Joining a plan
- Medicare.gov: Choosing a Medigap Policy (PDF)
- Medicare.gov: How Medigap works
- Medicare.gov: Guaranteed issue rights
- KFF: Medigap Guaranteed Issue Requirements: An Overview of Federal and State Rules (Oct 13, 2026)
- KFF: Medicare Advantage Out-of-Pocket Limits: Variation and Trends
- KFF: Medicare Advantage in 2026: Premiums, Out-of-Pocket Limits, Supplemental Benefits, and Prior Authorization
- KFF Health News: In Switching to Original Medicare, Beware of Medigap Plan Refusals (Mar 16, 2026)
- NAIC: State Medigap Rules, "Birthday Rule" and Coverage for under 65 (as of May 11, 2026) (PDF)
- Virginia SCC: Medigap Open Enrollment "Birthday Rule"
- Indiana SHIP: Ask SHIP (July 2026) (PDF)
- CMS: 2026 Medicare Trustees Report (June 9, 2026), Appendix V.E, Tables V.E1 and V.E2
- CMS: CY 2027 Rate Announcement, Attachment V (final Part D benefit parameters)
- SHIP National Technical Assistance Center: find your State Health Insurance Assistance Program
General information only. Medigap Atlas does not sell, recommend or enroll anyone in any plan, and is not affiliated with Medicare, CMS or any insurer. Rules and dates change and vary by state. Confirm your options with 1-800-MEDICARE (1-800-633-4227) or your State Health Insurance Assistance Program (SHIP) before you change coverage.