How do I get health insurance if I retire before 65?

Since Medicare doesn't start until 65, early retirees need a bridge. The most common option is an ACA marketplace plan at healthcare.gov, where premium tax credits are tied to your income – and because you control your taxable income in retirement, you can deliberately keep it low enough to qualify for large subsidies, sometimes paying very little. Other paths include COBRA from your former employer (full price for up to 18 months), a working spouse's plan, or a part-time job that offers benefits. This 'subsidy management' is a key reason some retirees keep income low in early years rather than doing aggressive Roth conversions. Map out a few years of an ACA bridge before you set your retirement date, since healthcare cost is often the biggest swing factor in retiring early.