Year-end to-do lists often look pretty similar from one annual roundup to the next, because many of us need repeated encouragement to do the right thing. Retirement-planning checklists are no exception. But this December, I want to offer some advice that may not have popped up on your radar and that could save you big money.

If you get prescription drugs through Medicare, now s the time to shop for a better plan. Since 2006, when Medicare began covering prescriptions, seniors enrolled in the so-called Part D have been able to change or drop their coverage during an annual open enrollment period that starts on Nov. 15 and ends on Dec. 31. (Medicare Advantage health plans, which typically offer extra benefits for higher premiums, also have open enrollment, from Jan. 1 through Mar. 31.)

Open enrollment was supposed to ensure that beneficiaries would switch to the plans that best suited them, while insurers would compete to provide the most popular medications at the lowest costs. Unfortunately, the opposite has happened. Insurance companies have boosted prices. For instance, the average premium for the Humana [HUM] Standard prescription-drug plan has rocketed 329 percent since 2006, according to the Kaiser Family Foundation. (Humana says every plan s premiums are based on the claims experience of their members, and that its plans have benefits that save members money.) Seniors, on the other hand, have stayed put. Twenty-five million Americans get prescriptions through Medicare, but just 1 million changed plans last year, according to the Government Accountability Office.

Despite rising costs, most Medicare beneficiaries say they re satisfied with their drug coverage. But although I hesitate to criticize freely made choices, it s clear that many seniors don t have a full understanding of the alternatives. That s largely because much of the information beneficiaries get from Medicare itself is overly complicated and not personalized, leaving them reliant on the insurance companies for guidance. And their medications are heavily subsidized the federal government pays for an average of 74.5 percent of coverage which hides the costs of bad decisions. A 2008 Brookings Institution study found that seniors generally did not know much about Medicare drug plans and did not actively research them. As a result, only a tiny fraction of enrollees chose the lowest-cost prescription-drug plan available to them 6 to 9 percent, according to
a report by the Kaiser foundation. That research concluded that seniors could have saved an average of $360 to $520 on prescriptions in 2006 if they had picked cheaper plans.

Medicare Part D premiums are still rising, while the range of drugs included in the plans cheapest coverage is declining, but both changes are happening unevenly. For example, the six biggest plans in the U.S. increased premiums by anywhere from 8 percent to 64 percent this year, according to Kaiser. And copayments increased by an average of $1 to $13 per prescription, depending
on the drug and type of plan, according to research firm Avalere Health. So there s no reason for you to assume that the plan that fit your needs in 2009 will be the best for you in 2010. The good news is, you can visit Medicare s Prescription Drug Plan Finder (www.medicare.gov) or call its help line (800-633-4227) to find plans with coverage, premiums and out-of-pocket charges that match your needs.

Tomorrow: Let your retirement plan sit.

Contributing editor Peter Keating can be reached at newretirement@hearst.com .