Medicare doesn't start until 65. If the math says you can retire at 58, or 60, or 62, that's a real gap, sometimes several years, where you need health coverage from somewhere else. This is one of the most overlooked pieces of an early retirement plan, and it deserves to be budgeted for specifically, not assumed away.
I've seen the mindset that leads to this gap up close, in my own family and among friends' parents: an assumption that Social Security and Medicare will simply take care of things once retirement arrives. Medicare helps enormously once it starts, but even then it isn't complete coverage on its own, and it doesn't exist at all in the years before 65. Assuming it will be there to catch you, without a specific plan for the years before it actually kicks in, is exactly the kind of gap that turns an otherwise solid retirement plan into a stressful one.
Option 1: COBRA
COBRA lets you keep your employer's health plan for a limited period after leaving, typically up to 18 months. The coverage is the same you had while working, but you now pay the full premium yourself, including the portion your employer used to cover, plus an administrative fee. It's often the most expensive option, but it means no disruption in coverage or providers during the transition.
Option 2: the ACA marketplace
The Affordable Care Act marketplace is where most early retirees end up for the stretch beyond COBRA's limited window. Plans are available regardless of health history, and the cost depends heavily on your household income for that year, since subsidies are income-based. This is actually a place where the withdrawal order article matters directly: how you structure your income in these years can materially change your healthcare costs, since drawing down a taxable account for a period can keep reported income low enough to qualify for meaningful subsidies.
Your reported income in early retirement is as much a healthcare cost question as it is a tax question. Keeping taxable income low in these years can lower marketplace premiums significantly.
Budget for it as its own line item
Healthcare costs before 65 can be a meaningful chunk of an early retirement budget, easily comparable to housing costs in some cases. Treating it as a specific number to plan for, rather than an assumed continuation of what you paid while employed, keeps the rest of the retirement plan honest.
Once 65 arrives
Medicare becomes available at 65 regardless of when you actually stop working, and it's worth enrolling on time even if you're still employed, since late enrollment can carry permanent penalties depending on your situation. It won't cover everything, supplemental coverage is common, but it's a significant cost reduction from the bridge years.
Retiring before 65 means planning for a real healthcare gap, not assuming it away. COBRA and the ACA marketplace are the 2 main bridges, and how you structure your income during those years can materially affect what the marketplace option actually costs you. Budget for this specifically as part of any early retirement plan.