Maryland’s Medicare Supplement open enrollment period is a one-time, six-month window that starts the first day of the month you are both 65 and enrolled in Medicare Part B, and it gives you the strongest protections you will ever have to buy a Medigap policy. Two other windows let you buy or switch later without medical underwriting: Maryland’s annual birthday rule for existing policyholders, and federal guaranteed issue rights triggered by certain life events. Each has its own rules and deadlines, and missing a window usually means an insurer can review your health, charge more, or turn you down.
The Six-Month Window at Age 65
Your six-month open enrollment period begins on the first day of the month you turn 65 and are enrolled in Part B.1Medicare.gov. When Can I Buy a Medigap Policy During this window, every insurer selling Medigap in Maryland must accept your application regardless of your health history. They cannot charge more because of a medical condition, and they cannot make you wait for coverage of pre-existing conditions as long as you have at least six months of prior creditable coverage.2Legal Information Institute. Maryland Code of Maryland Regulations 31.10.06.06 – Open Enrollment
The window is tied to your Part B enrollment date, not your birthday alone. If you delayed Part B because you had employer coverage, the six-month clock starts when you eventually sign up for Part B after turning 65. You can apply for any standardized Medigap plan sold in Maryland during this window.
Once the six months expire, insurers can require medical underwriting outside of the other two windows described below. That means they can review your health history, charge higher premiums, or decline your application entirely.
Maryland’s Birthday Rule
Since July 1, 2023, every existing Medigap policyholder in Maryland gets a yearly 30-day window that begins on their birthday.3Maryland Insurance Administration. Medicare Supplement Monthly Premiums During this period, you can switch to a different Medigap plan with equal or lesser benefits without medical underwriting. You can switch carriers, not just plans within your current insurer.
“Equal or lesser benefits” means you can move down in coverage but not up. If you hold Plan G, you could switch to Plan A, B, D, K, L, M, or N, but not up to Plan F. The Maryland regulation includes a chart mapping each plan to its eligible alternatives.2Legal Information Institute. Maryland Code of Maryland Regulations 31.10.06.06 – Open Enrollment
One detail worth knowing. If you were medically underwritten when you first bought your policy and received less than the preferred rate, you are entitled to the preferred rate during this birthday window.3Maryland Insurance Administration. Medicare Supplement Monthly Premiums That alone can make the annual shopping exercise worthwhile even if you stay on the same plan letter.
Insurers must send written notice of your birthday rule rights at least 30 days, and no more than 60 days, before your birthday. If you never received that notice, contact the Maryland Insurance Administration; the insurer is required to provide it.
Guaranteed Issue Rights After a Qualifying Event
Outside the two windows above, you can still buy a Medigap policy without medical underwriting if a qualifying life event gives you guaranteed issue rights.4Medicare.gov. Get Ready to Buy In these situations, insurers cannot turn you down or charge more based on your health. Common triggers include:
- Losing employer or union group coverage that supplemented Medicare, whether because you retire, the employer drops the plan, or you lose eligibility.
- Your Medicare Advantage plan leaves your service area, stops providing care in your area, or you move out of its coverage area.
- You joined a Medicare Advantage plan when you first became eligible for Medicare and decide to switch back to Original Medicare within the first year.
- Your current Medigap company becomes insolvent, or you dropped a Medigap policy because an insurer or agent misled you.
These rights generally require you to apply within 63 days of losing prior coverage or the triggering event. The deadline is strict. Miss it and you lose the guaranteed issue protection, which puts you back into the standard underwriting process where your health history matters.
If You Are Under 65 on Medicare
Federal law does not require insurers to sell Medigap policies to people under 65.1Medicare.gov. When Can I Buy a Medigap Policy Maryland goes further. State law requires carriers to make certain Medigap plans available to people under 65 who qualify for Medicare because of a disability.5Justia Law. Maryland Insurance Code 15-909 – Open Enrollment
The Maryland Insurance Administration’s current rate guide lists Plans A, C, and D as available to under-65 disabled beneficiaries, and some carriers voluntarily offer additional plan letters.3Maryland Insurance Administration. Medicare Supplement Monthly Premiums Under-65 applicants get the same six-month open enrollment protection, starting when they enroll in Part B. During that window, carriers cannot deny coverage or charge more based on health.
Premiums for under-65 policyholders tend to run higher than those for people 65 and older. Maryland caps what carriers can charge for Plan A at no more than the average premium paid by all policyholders aged 65 and older in the state on that same plan form.5Justia Law. Maryland Insurance Code 15-909 – Open Enrollment That keeps Plan A within reach for younger disabled enrollees.
What Happens If You Apply Outside These Windows
If none of the three windows applies to you, Maryland insurers can require medical underwriting on a new Medigap application. They can review your health history, quote you a higher premium, or deny coverage outright. This is the single biggest enrollment mistake people make with Medigap: assuming they can sign up whenever they want and get the same deal offered at 65. They cannot. Knowing which window you are in, and the deadline that governs it, is what preserves your right to buy coverage on the same terms as anyone else.