Most people who are about to retire have very little working knowledge about Medicare, and when they should enroll. A recent article in the New York Times highlights when you must enroll in order to prevent penalties.
In a nutshell, you normally have seven months — the month in which you turn 65 and the three months both before and after it — to apply for Part B without penalty. This is true even if your normal retirement age is 66 or 67. However, if you are still employed at age 65, and working at a company or organization with 20 or more employees (or your spouse is), and covered by an employee health plan, you may not need Part B yet. Instead of paying premiums, it could make financial sense to hold off. But it’s important to know that after losing employee coverage — due to retirement, layoffs or any other reason — you have an eight-month “special enrollment period” to sign up for Part B.