Key money birthdays
The dates after 40 that matter for your savings, Social Security and Medicare. Missing some of them costs money for life.
Your key money birthdays
From SSA, Medicare.gov and IRS rules, checked November 5, 2026. General information, not financial advice.
Born on the 1st of a month? Social Security counts you as born the month before. Your own dates and amounts are in your free my Social Security account at ssa.gov/myaccount.