The California Birthday Rule

Equal or lesser benefits is the whole game

The one real constraint is the direction of travel. You may move to a plan with the same or fewer benefits. You may not use this window to upgrade.

• Plan G to Plan N. Permitted. Plan N is the lesser benefit. Someone whose premium has climbed uncomfortably can step down every year without a health question.

• Plan G to another company's Plan G. Permitted. Equal benefits, different carrier, different premium. This is the most common use of the rule and the one that saves people the most.

• Plan N to Plan G. Not permitted under this rule. That is an upgrade, and it normally requires medical underwriting.

• Plan F to another company's Plan F. Permitted for someone who already holds Plan F, since equal benefits are allowed and holding the policy means they were eligible for Medicare before it closed to new enrollees on January 1 2020. It does not open Plan F to anyone who became eligible on or after that date.

This asymmetry is exactly why we usually steer people toward the richer plan first. It is covered in full on Plan G vs Plan N.

What the birthday rule is not

• It is not a way to get a supplement if you do not have one. You must already hold a Medicare Supplement policy for the window to exist. Someone on a Medicare Advantage plan does not get a birthday window to move to a supplement.

• It does not apply to Medicare Advantage plans. Advantage changes run on their own calendar: the Annual Enrollment Period, October 15 to December 7, and Medicare Advantage Open Enrollment, January 1 to March 31, plus any special enrollment period you qualify for.

• It does not touch Part D. Prescription drug plans have their own enrollment windows and are changed separately. It is worth reviewing the drug plan every autumn regardless, because formularies change yearly.

• It is not the only route. Guaranteed issue rights from losing coverage, from a plan leaving your area, or from a network change carry their own windows, commonly 63 days, and they can be more generous than the birthday rule because some of them do allow moving up.

Why so few people use it

The rule has been on the books for years and was broadened in 2020 to lengthen the window and to allow moves between carriers rather than only within one. And yet most people who are entitled to it never use it once.

The reason is structural rather than sinister. A carrier has no commercial interest in reminding you that you may take your business elsewhere without answering a single health question. Carriers are required to notify policyholders about the window, and they do, and the notice arrives as one more piece of insurance post in a year full of it. Nobody reads it, because everything from an insurance company looks the same.

Meanwhile Medigap premiums do not stay still. A block of business closed to new members ages, its claims rise, and its rates rise with it. Someone who bought well at 65 and never looked again may be paying substantially more than a healthy new applicant, for a policy with benefits fixed by law to be identical. The birthday rule exists precisely to fix that, and it goes unused.

How we handle it

For our supplement clients this is a standing item. We know your birthday, we know what you hold, and we look at the market for you as your window approaches rather than waiting for you to ask.

If you hold a supplement bought somewhere else, we are still happy to look. There is no charge and no obligation, and if the answer is that you already have the best available rate for your plan, we will say so and you will have lost nothing but a phone call.