Medigap Birthday Rule in 2026: Illinois 45 Days vs Federal 63-Day Rights
Two different protections let you change a Medicare Supplement policy without health questions, and they work nothing alike. Here is what a state birthday rule does, what federal guaranteed issue rights do, and how Illinois and Maryland differ.
The short answer
A birthday rule is state law. Illinois gives Medigap policyholders a 45-day window starting on their birthday to move to an equal or lesser policy from the same issuer or an authorized affiliate. Maryland runs an annual guaranteed issue period and does not make you stay with your current carrier. Federal guaranteed issue rights are separate, triggered by losing coverage, and most last 63 days.
- Illinois: 45-day annual window that begins on your birthday, same issuer or an authorized affiliate, equal or lesser benefits
- Maryland: annual period to change to a Medicare Supplement policy of equal or lesser benefits, and you do not have to stay with your current carrier
- Federal guaranteed issue: triggered by events such as losing employer coverage, and most rights run 63 days
- Medigap open enrollment: one 6-month window that starts the first month you are 65 or older and enrolled in Part B
Applies to people who already hold a Medicare Supplement policy in a state with an annual birthday rule, including Illinois and Maryland, and to anyone deciding whether to apply under a federal guaranteed issue right instead; rules and available plans vary by state, so confirm yours before applying.
What does the Medigap birthday rule actually change?
A birthday rule is state law. It gives people who already hold a Medicare Supplement policy a short annual window to change policies without medical underwriting. It does not come from Medicare, and it does not exist in most states.
Two limits show up in almost every version. The new policy must carry benefits equal to or lesser than the one you hold, and you must apply inside the window. Miss the dates and you are back to health questions.
That matters because federal law gives you only one underwriting-free shot at Medigap. Your six-month Medigap open enrollment period starts the first month you have Part B and are 65 or older, and it does not repeat every year. Inside it, an insurance company cannot refuse to sell you a policy because of a health problem or charge you a higher premium based on health status. If you are still choosing a plan letter, our breakdown of how Plan G, Plan N and Plan K compare covers the tradeoffs.
How is a birthday rule different from federal guaranteed issue rights?
Guaranteed issue rights are federal protections triggered by an event, not a date on the calendar. Losing employer or union retiree coverage, your Medicare Advantage plan leaving your area, or an insurer misleading you can each open one. Most of those rights last 63 days from the day the old coverage ends.
A birthday rule is the opposite. Nothing has to go wrong. You simply hold a policy, your birthday arrives, and the window opens on schedule every year.
There is one federal right people mix up with a birthday rule: the trial right. People who disenroll from Medicare Advantage within 12 months of first enrolling have a right to buy a Medigap policy without regard to medical history, and after 12 months they can be denied or charged more. We walk through that clock in our post on switching from Medicare Advantage to Medigap and the 63-day rule.
| Protection | How long | How often | What you can buy |
|---|---|---|---|
| Medigap open enrollment | 6 months | One time, at 65 or older with Part B | Any policy the insurer sells in your state |
| Federal guaranteed issue right | 63 days in most situations | Each qualifying event | Specific plan letters tied to your situation |
| Illinois birthday rule | 45 days | Every year, ages 65 to 75 | Equal or lesser policy, same issuer or affiliate |
| Maryland birthday rule | Birthday plus the days after it | Every year | Equal or lesser policy, any carrier |
How does the Illinois birthday rule work?
Illinois requires an annual open enrollment period lasting 45 days that begins on the policyholder’s birthday, during which the person may buy a Medicare supplement policy from the same issuer with benefits equal to or lesser than the previous coverage. The Illinois Department on Aging describes the same 45 days as applying to the same company or issuer, or any affiliate authorized to transact business in Illinois.
The age cap is the part people miss. Illinois requires insurers to notify policyholders under the age of 75 of their right to choose a different Medicare supplement plan with that company. Someone at 78 cannot use the rule.
The state guide notes that Public Act 103-0747 was revised with new updates starting January 1, 2026, so confirm the current terms before you apply. Illinois also designates a year-round guaranteed issue insurer. The 2026 state guide identifies Blue Cross Blue Shield of Illinois as a guarantee issue company for 2026, selling to anyone over 65 in any health condition at the same premium rate as others in the same policy class, and that guide notes the same company also has some plans with underwriting. Readers weighing the other side of the coin can review our look at Medicare Advantage plans in Illinois for 2027.
How does the Maryland birthday rule work?
Maryland established a guaranteed issue period each year that lets a policyholder change, without underwriting, to a Medicare Supplement policy of equal or lesser benefits, and you do not have to stay with your current carrier. That carrier freedom is the main difference from Illinois.
You should also get a heads-up in the mail. Insurers must send each Medicare Supplement policyholder an annual notice of the right to switch policies at least 30 days, but not more than 60 days, before the birthday. Treat that letter as your signal to start comparing.
What counts as equal or lesser is not a judgment call. The Maryland Insurance Administration publishes a chart showing existing plans and the corresponding plans that have lesser or equal value. Check your plan letter against that chart first [VERIFY: confirm the exact Maryland window length and effective date on the MIA birthday rule page].
Why does attained-age pricing make this window matter?
Medigap benefits inside a plan letter are standardized, so a Plan G is a Plan G. Price is where insurers differ, and pricing method decides how your premium behaves over time.
Attained-age policies are priced on your current age, so the premium climbs as you get older, on top of general rate increases. Issue-age policies are priced on your age when you bought. Community-rated policies charge the same base premium regardless of age. The CMS guide Choosing a Medigap Policy explains all three, and which methods insurers may use depends on your state.
If you hold an attained-age policy at 72, your rate is doing what it was designed to do. An annual underwriting-free window is your realistic chance to react to it. We never quote a rate in an article, because Medigap premiums vary by state, insurer, age and discounts.
How do you switch plans during your window?
Order matters more than speed. An application filed inside the window still counts if the insurer is still processing it after the window closes, but a late application does not.
Your birthday window checklist
- Write down your plan letter, your insurer, and the exact date your window opens and closes.
- Confirm the policy you want qualifies as equal or lesser under your state’s definition.
- In Illinois, confirm the new policy is with your issuer or an affiliate authorized in the state.
- Compare filed premiums and rate-increase history for the same letter, not just the first-year figure.
- Apply inside the window and keep a dated copy of the application.
- Keep your current policy in force until the new one is approved and effective.
What if your state has no birthday rule?
Then your options are the six-month Medigap open enrollment period, a federal guaranteed issue right, or medical underwriting. Medigap insurers must issue policies to people 65 or older without regard to health status when they first enroll, but applicants with pre-existing conditions may be denied or face higher premiums in most states after their first six months of Part B enrollment.
A handful of states add annual or anniversary protections, and the window length, carrier rules and age limits are not the same in any two of them. Guaranteed issue and underwriting standards vary by state, so check your state insurance department before assuming a rule you read about applies to you.
If you are still weighing whether a supplement fits at all, read our honest comparison of Medicare Advantage and Medigap, then use our Medicare hub for enrollment dates and Part D basics. We work by phone and video in more than 40 states, including Illinois and Maryland, and we are not licensed in California.
Questions people ask
Can I use a birthday rule to move to a plan with richer benefits?
No. Both the Illinois and Maryland rules limit you to a policy with benefits equal to or lesser than what you already hold. Moving up a plan letter outside a guaranteed issue right generally means medical underwriting, and the insurer can decline the application.
Does the fall enrollment period let me change my Medigap policy?
No. Medicare AEP runs October 15 to December 7 and covers Medicare Advantage and Part D choices. Medicare Supplement policies are governed by your six-month Medigap open enrollment period, federal guaranteed issue rights, and any state rule, not by AEP dates.
Does the birthday rule apply if I have a Medicare Advantage plan?
No. A birthday rule protects people who already hold a Medicare Supplement policy. If you have Medicare Advantage and want a Medigap policy, you generally need a guaranteed issue right, a trial right, or approval through underwriting.
Will switching under the birthday rule lower my premium?
Not necessarily. The rule removes medical underwriting from a qualifying switch. It does not set the rate. Compare the actual filed premium for the new policy, including any household or payment discounts, before you sign anything.
What if I miss my window by a few days?
You wait until your next birthday window or apply with underwriting. In Illinois the application must be made inside the 45 days, so a late file loses the protection for that year. Set a calendar reminder two weeks before your birthday.
Do these rules apply to people under 65 on Medicare?
It depends on the state. Illinois publishes separate under-65 access rules, and Maryland limits which plan letters are open to under-65 beneficiaries. Ask your state insurance department or SHIP which policies your situation allows before you apply.
Sources
- Choosing a Medigap Policy: A Guide to Health Insurance for People with Medicare, Accessed September 25, 2026
- Illinois Department of Insurance, Medicare Supplement filing requirements, Accessed September 25, 2026
- Illinois Department on Aging, Medicare Choices Guide for 2026, 2026
- Maryland Insurance Administration, Medicare Birthday Rule, Accessed September 25, 2026
- Maryland Insurance Administration, Medicare Supplement Rate Guide, Accessed September 25, 2026
Not sure which window you are actually in
We are an independent agency licensed in more than 40 states, and we work by phone and video. Tell us your birthday, your plan letter, and your state, and we will confirm whether a state birthday rule, a federal guaranteed issue right, or underwriting applies to your situation.
Talk to a licensed agentCall or text (773) 657-9140Smart Insurance Agents LLC is an independent, licensed insurance agency and is not connected with or endorsed by the U.S. government or the federal Medicare program. We do not offer every plan available in your area. Please contact Medicare.gov, 1-800-MEDICARE, or your local State Health Insurance Assistance Program for information on all of your options. Content is for general information and is not a guarantee of coverage or rates; figures are subject to change by CMS and carriers.