While the government's insurance plan makes health care affordable for millions, many seniors make costly mistakes when signing up.
"People are just confused about choices, and there are so many choices out there that they just don't know what to do," said Akila Gibbs, the executive director of the Pasadena Senior Center.
When you turn 65, you're required to sign up for Medicare. Because everyone's medical needs are different, the plan you select should fit your specific needs.
"The No. 1 mistake is not paying attention and just falling onto original Medicare when it may not be the best choice for you," said David Sayen of the U.S. Centers for Medicare and Medicaid.
Another mistake is that when you sign up and don't choose Medicare Part B, which covers doctor's visits, or Part D, which is prescription drug coverage, your premium will be slightly higher.
If you're still working and have health coverage from your job, you're not required to enroll, but, that could be a big mistake. Medicare Part A, which covers hospitals, is free and it may pick up expenses your own plan doesn't cover. If you have a high-deductible plan, Part B may pick up costs before your deductible even kicks in.
Another mistake is failing to sign up for coverage if you turn 65, but your spouse is still working and has a health plan through their job. Once they retire, you have just eight months to enroll or you could be without Part B coverage for 3 to 15 months.
"If you delay, you may find yourself without health insurance when you need it and when you do sign up you would face a higher premium for signing up later than you otherwise could have," Sayen said.
Gibbs advises first-time Medicare enrollees to do their homework.
"They should educate themselves, because if they don't at 65, they may have to live with those choices forever," she said.
Remember: you have until Dec. 7 to sign up for coverage.