In most states, switching Medicare Supplement (Medigap) plans after your first 6 months on Medicare means going through medical underwriting. If you have health issues, you may be denied or charged more. But a handful of states have what's called a birthday rule that gives you a yearly window to switch with no health questions. If you live in one of these states, it's a yearly opportunity worth knowing about.
What is the Medigap birthday rule?
The birthday rule is a state law that lets people on Medicare Supplement (Medigap) plans switch to a different Medigap plan once a year around their birthday, without going through medical underwriting.
Normally after your initial 6-month Medigap Open Enrollment Period at 65, you have to answer health questions to switch carriers or plans. If you have diabetes, heart disease, or other chronic conditions, you may be denied or quoted a much higher rate. The birthday rule eliminates that barrier.
This is unique to certain states. Most states do not have one. If you live in a state with a birthday rule, you have a yearly chance to save money or upgrade coverage.
States with a Medigap birthday rule (2026)
California
California was the first state with a birthday rule and has the most generous one. You can switch to any Medigap plan with equal or lesser benefits than your current plan. The window is 60 days starting on your birthday.
You can use the rule every year. The new plan starts on the first of the month after you apply.
Oregon
Oregon's birthday rule gives you 30 days starting on your birthday to switch to a plan with equal or lesser benefits with the same or different carrier. No medical underwriting.
Idaho
Idaho added a birthday rule in 2022. You get 63 days starting on your birthday to switch to a Medigap plan with equal or lesser benefits at the same level (Plan G to Plan G, Plan N to Plan N).
Illinois
Illinois has a 45-day window starting on your birthday. You can switch to the same letter plan (Plan G to Plan G) with any carrier with no underwriting.
Kentucky
Kentucky's birthday rule gives you 60 days starting on your birthday. You can switch to any plan with equal or lesser benefits with no underwriting.
Louisiana
Louisiana lets you switch within 63 days of your birthday to a plan with equal or lesser benefits.
Maryland
Maryland's rule gives you a 31-day window starting on your birthday. You can switch to the same plan with a different carrier.
Nevada
Nevada gives you 60 days starting on your birthday to switch to a Medigap plan with equal or lesser benefits.
Oklahoma
Oklahoma added a birthday rule in 2022. You get 60 days starting on your birthday to switch to a plan with equal or lesser benefits.
Washington
Washington's birthday rule is one of the most flexible. There's no specific birthday window. Anyone on Medigap can switch carriers or plans within 90 days of any major event, and many residents can switch year-round.
How the birthday rule actually works
Step 1: Figure out if you qualify
Confirm you live in a birthday rule state. Confirm your current Medigap plan is still in force.
Step 2: Compare quotes from other carriers
The same plan letter (like Plan G) has identical benefits across all carriers. Only the price differs. Get quotes from 3 to 5 carriers in your state for your exact age and zip code. You can do this with an independent Medicare agent or use online comparison tools.
Step 3: Find a plan with equal or lesser benefits
In most birthday rule states, you can only switch to a plan with equal or lesser benefits than what you currently have. So if you have Plan G, you can switch to another Plan G (same benefits) or Plan N (lesser benefits). You usually cannot upgrade from Plan N to Plan G during the birthday rule window.
Step 4: Apply during your window
Submit your application during the state-specific window. Mark your calendar.
Step 5: New plan starts the next month
Once approved, your new plan starts the first of the month after you apply. Your old plan ends automatically.
Why this matters
Medigap rates increase every year. Carriers raise prices 5 to 15 percent annually. The plan you bought 5 years ago might cost a lot more today than a comparable plan from a different carrier.
Without a birthday rule, switching means medical underwriting. If you have any health issues, you might be denied. With a birthday rule, you can shop your Medigap every year and switch to whichever carrier has the best price for the same benefits.
Real example: A Plan G customer in California pays $200/month with Carrier A. Carrier B offers the same Plan G for $140/month. Without the birthday rule, switching requires passing health questions. With the birthday rule, the switch is guaranteed. That saves $720/year for the same exact coverage.
Common mistakes
Mistake 1: Missing the window
Birthday rule windows are short (30 to 90 days depending on the state). Set a reminder a month before your birthday. Get quotes in advance.
Mistake 2: Switching to a plan with worse benefits without realizing
Most birthday rule states only let you switch to a plan with equal or lesser benefits. Plan G has more benefits than Plan N. Plan N has more benefits than Plan K or L. Switching from Plan G to Plan N is allowed under the birthday rule. Switching from Plan N to Plan G is not.
Read the plan letter requirements for your specific state before switching.
Mistake 3: Trusting the cheapest quote alone
Cheaper today doesn't mean cheaper tomorrow. Look at the carrier's rate increase history and financial strength rating. A carrier with low rates now but a history of 12 percent annual increases will cost more in 3 years than a stable carrier.
States without a birthday rule
Most states do not have a birthday rule. Some states have other Medigap protections:
- Connecticut, Maine, Massachusetts, New York: Continuous open enrollment or modified community rating with year-round guaranteed issue rights
- Vermont: Carrier-issued open enrollment windows
- Missouri: Anniversary rule allows switching within 30 days of plan anniversary
What to do this year
- Check if your state has a birthday rule (see the list above)
- If yes, mark your birthday window in your calendar
- Two months before, get fresh Medigap quotes from 3 to 5 carriers
- If you find a better deal on the same plan letter, apply during your window
- If your state does not have a birthday rule, ask an independent agent if there are any guaranteed issue rights you can use
The bottom line
The Medigap birthday rule is one of the most underused protections in Medicare. If you live in a state with one, you have a yearly chance to save hundreds of dollars without medical underwriting. Most members never use it because they don't know it exists. Mark your birthday window and shop your Medigap every year.
