The windows, and which ones close for good

Medicare is full of dates. Most of them are softer than they sound. Two of them are not, and the difference is the single most useful thing on this website.

This guide sorts them out. It carries no figures, because premiums, penalties and thresholds change every year and a stale number is worse than no number. For any amount, use Medicare.gov or telephone 1-800-MEDICARE.

The window around your 65th birthday

The first window opens three months before the month you turn 65, includes that month, and closes three months after it. Seven months in total.

Inside it you can sign up for Part A and Part B without being asked a single question about your health, and without a late penalty. It is the ordinary, intended route on to Medicare.

If you are already drawing Social Security when you approach 65, you are usually enrolled automatically and a card arrives in the post. If you are not drawing Social Security, nothing happens on its own. Nobody telephones you. The window opens and closes quietly, and a surprising number of people miss it because they were waiting to be told.

There is one important exception, covered further down: if you are still working and covered by an employer plan, the rules change.

The window that closes for good

Here is the one that catches people.

When your Part B begins, a separate six-month clock starts. During those six months, a Medicare Supplement — a Medigap policy — must sell you a plan regardless of your health. The insurer cannot ask about your diabetes, your knee, or the thing you had looked at last spring. It cannot charge you more because of any of it, and it cannot refuse you.

This is called your Medigap open enrolment period, and when it ends, in most states it is over permanently.

After it closes, an insurer may put you through medical underwriting. They can ask health questions, they can charge more, and they can decline you outright. Plenty of people are still accepted afterwards. Plenty are not, and there is no appeal, because the insurer is entitled to say no.

We are not raising this to hurry you. We are raising it because it is genuinely irreversible, and almost nothing else in Medicare is. If you are approaching 65, or your Part B is about to start after leaving an employer plan, this is the conversation to have early rather than late.

Ohio, Kentucky and Indiana each have their own supplement rules layered on top of the federal ones. Ask before you assume your state does something a neighbouring one does.

The drug-coverage clock

Part D has a different kind of deadline. It is not a door that closes — it is a meter that runs.

If you go without creditable drug coverage after you were first eligible, and later decide you want it, a late enrolment penalty is added to your premium. The penalty is permanent. It is recalculated each year, and you pay it for as long as you have drug coverage.

“Creditable” is the word doing the work. Coverage from an employer, a union or the Veterans Administration often counts, and if it counts you can delay Part D with no consequence at all. Your plan is required to tell you in writing whether it is creditable. Keep that letter. If you cannot find it, ask the plan administrator for another copy and keep that one.

People sometimes decline drug coverage on the reasonable grounds that they take no medications. It is reasonable and it is usually a mistake, because the penalty is calculated from how long you went without, not from what you needed at the time.

The windows you can catch later

The rest are gentler, and they come round again.

Annual Enrollment, 15 October to 7 December. This is the one the television advertisements are about. You can join, switch or leave an Advantage plan, and join, switch or leave a drug plan. Changes take effect on 1 January. Miss it and you wait a year, which is inconvenient rather than serious.

Medicare Advantage Open Enrollment, 1 January to 31 March. If you are already in an Advantage plan you get one change: switch to a different Advantage plan, or go back to Original Medicare and pick up a drug plan. This one does not let you join an Advantage plan from Original Medicare.

General Enrollment, 1 January to 31 March. For people who missed their first window entirely and have no other route in.

The windows that open when life changes

Some events open a special enrolment period outside all of the above. Moving out of your plan’s service area. Retiring and losing employer coverage. A spouse dying and their coverage ending with them. Entering or leaving a nursing home. Your plan leaving your county.

These windows are typically two months long and they are easy to miss, because the event itself is usually consuming your attention. If something in that list has happened to you, telephone somebody — us, your SHIP counsellor, or 1-800-MEDICARE — within a week or two rather than a month or two.

What to do about all of this

If you are turning 65 in the next year, put your seven-month window in the calendar on the wall, and mark the start of it, not the end.

If you are still working past 65, do not act on any of this until you have had the employer question answered properly. It is the subject of its own guide.

If you are already on Medicare and someone tells you a deadline is tonight, they are selling something. The real deadlines are published, they are the same for everybody, and none of them arrives without warning.

Bring your list of doctors and prescriptions to any conversation about dates. It is astonishing how often “when should I do this” turns out to depend on what you take and who you see.