Retiring at 55: the rule of 55, the healthcare gap, and the real math

Early retirees have four main penalty-free paths, each with sharp edges:

• Rule of 55 — leave your employer in or after the year you turn 55 and withdraw from that employer's 401(k)/403(b) penalty-free (ordinary income tax still applies). Roll that money to an IRA and you lose the exception.
• Taxable brokerage accounts — no age rules at all, and long-term gains get preferential rates. This is why early-retirement plans lean heavily on taxable savings.
• Roth contributions — your original Roth IRA contributions (not earnings) can come out any time, tax- and penalty-free.
• 72(t) / SEPP — a schedule of 'substantially equal periodic payments' from an IRA, penalty-free at any age, but rigid: break the schedule and penalties apply retroactively.

From 55 to 65 you'll buy your own coverage, usually on the ACA marketplace. The decisive variable is your reported taxable income, because subsidies are means-tested against it. Early retirees who fund spending from taxable savings and Roth dollars can report low income and qualify for substantial premium help; the same spending funded from pre-tax withdrawals may cost thousands more per year in both taxes and lost subsidies. Over a ten-year bridge, income sequencing is often worth more than investment performance.

A 4% withdrawal rate was validated against 30-year retirements; over 40+ years, most research points to initial rates closer to 3.25–3.5% for the same confidence — meaning early retirees need roughly 28–30x annual spending rather than 25x. Flexible spending rules (guardrails) claw much of that back: a retiree willing to trim spending 10% in bad markets can safely start meaningfully higher than one who won't.

The other 40-year variable is optionality: part-time income in the first decade, even $15,000–$20,000 a year, reduces early withdrawals during the years when sequence-of-returns risk is highest — often doubling a plan's resilience.