Best Medicare Part D Prescription Drug Plans in 2022

by Ann deBruyn

Medicare Part D plans cover prescription drugs. Medicare beneficiaries with Medicare Part A and/or Part B are eligible to buy a Part D plan to add prescription drug coverage to Original Medicare.

It’s best to sign up for Medicare prescription drug coverage as soon as you’re eligible, even though Part D is technically optional. If you don’t buy a Medicare Part D plan or a Medicare Advantage plan with prescription drug coverage, you’re responsible for the full cost of your medications, and there are permanent cost penalties if you sign up late.

Nerdy tip: Many Medicare Advantage plans, also called Medicare Part C plans, offer prescription drug coverage, so generally only Original Medicare members need to shop for a separate Part D plan. You can’t combine most types of Medicare Advantage plans with a stand-alone Medicare Part D plan. You can, however, purchase a Part D plan if you have a Medicare Supplement Insurance plan that doesn’t cover prescription drugs.

Best Medicare Part D plans for 2022

Unlike Medicare Part A and Part B, Part D plans are sold by private insurance companies, and the plans’ costs, benefits and other features can vary significantly. It’s important to confirm whether a plan covers your prescription drugs, then you’ll want to consider each plan’s strengths and weaknesses.

NerdWallet compares and evaluates Medicare prescription drug plans based on factors including quality ratings from the Centers for Medicare Medicaid Services, or CMS, prices, cost-sharing requirements, formulary design and more.

Here’s how the top Medicare Part D plans for 2022 stand out:

Best for overall quality: AARP/UnitedHealthcare Medicare Part D

Average Medicare Part D star rating: 3.9 stars.

Top quality measures that outperformed the national average:

  • Drug plan quality improvement.

  • Call center foreign language interpreter and TTY availability.

  • Few members choosing to leave the plan.

Standout feature: AARP/UnitedHealthcare Medicare Part D plans get the highest overall quality ratings from CMS among the large companies that insure nearly 90% of all stand-alone Medicare Part D plans.

Company overview: There are more than 4 million Medicare beneficiaries with AARP/UnitedHealthcare prescription drug plans — the third-highest total among Part D insurance companies.

AARP/UnitedHealthcare Medicare Part D plans are widely available and get solid quality ratings from CMS. Pricing for the highest-coverage AARP/UnitedHealth Part D plan can get expensive, however, and the plans’ ratings for helping members with their medications are below average.

Pros:

  • You can get an AARP/UnitedHealthcare Part D plan everywhere in the U.S. and in several U.S. territories.

  • AARP/UHC plans had few complaints and small numbers of members choosing to leave the plans.

  • The AARP MedicareRx Walgreens plan has no copays or deductible for Tier 1 generic drugs.

Cons:

  • AARP/UHC plans trailed the national average on quality measures related to making sure members are filling their prescriptions and managing their drugs.

  • The AARP MedicareRx Preferred plan has a lot of coverage, but its average monthly premium is higher than similar high-coverage options from competitors.

Best for low premiums: Aetna Medicare Part D

Average Medicare Part D star rating: 3.5 stars.

Top quality measures that outperformed the national average:

  • Drug plan quality improvement.

  • Few complaints about the drug plan.

Standout feature: Aetna offers the least expensive stand-alone Medicare Part D plan you can find, on average, in 2022.

Company overview: Aetna has more Medicare Part D members than any other company. It’s owned by parent company CVS Health and sells prescription drug plans under the SilverScript brand name.

Its Part D premiums are among the lowest on the market, but Aetna plans fall behind most competitors in quality ratings from CMS.

Pros:

  • Aetna’s SilverScript SmartRx plan has the lowest average monthly premium of any stand-alone Medicare Part D plan on the market.

  • The cost is the same whether you choose to get drugs in person or by mail.

Cons:

  • Aetna has below-average ratings from CMS on 10 out of 12 Medicare Part D quality measures.

  • The SilverScript SmartRx plan has low premiums, but it has higher copays than some competing plans.

Best for high-coverage, low-cost options: Cigna Medicare Part D

Average Medicare Part D star rating: 3.75 stars.

Top quality measures that outperformed the national average:

  • Medicare plan finder price accuracy.

  • Drug plan quality improvement.

  • Few members choosing to leave the plan.

Standout feature: Cigna’s high-coverage Part D plan is the cheapest among similar options from market leaders.

Company overview: Cigna is the fifth-largest company offering Medicare Part D plans. It offers some of the lowest prices for high-coverage Medicare Part D plans.

Overall star ratings from CMS for Cigna’s stand-alone Medicare Part D plans are about average.

Pros:

  • The Cigna Extra Rx plan is less expensive, on average, than similar high-coverage options from major competitors.

  • The Secure Rx and Extra Rx plans offer certain insulins with minimal cost-sharing.

  • Each of Cigna’s plans has no deductible for drugs on certain formulary tiers (specific tiers vary by plan).

Cons:

  • Cigna trailed the national average on quality measures related to helping members with conditions like diabetes and hypertension get and take their medications.

  • You’ll pay more to get some drugs in person — the lowest copays can require 90-day supplies by mail.

Best for $0-copay and $0-deductible options: Humana Medicare Part D

Average Medicare Part D star rating: 3.67 stars.

Top quality measures that outperformed the national average:

  • Call center foreign language interpreter and TTY availability.

  • Medication Therapy Management program completion rate for comprehensive medication review.

  • Few complaints about the drug plan.

Standout feature: Several Humana plans offer $0 copays and $0 deductibles for certain generic drugs.

Company overview: With about 3.5 million members, Humana is the fourth-largest company offering Medicare Part D plans. Humana’s Walmart Value Rx and Premier Rx plans have $0 deductibles for certain drugs, and its Basic Rx and Premier Rx plans have $0 copays for certain drugs. However, coinsurance for brand-name drugs could lead to higher out-of-pocket costs.

Humana’s overall star rating from CMS is close to average, but its plans fall short on two-thirds of CMS’ more detailed quality measures for Part D plans.

Pros:

  • Humana offers multiple options for plans with no copays or deductibles for generic drugs.

  • Humana Part D plans receive few complaints, and the company gets solid ratings on a third-party customer satisfaction survey.

Cons:

  • Humana charges coinsurance rather than copays for many drugs, which can get expensive.

  • Humana gets below-average ratings on eight out of 12 Medicare Part D quality measures.

Find the right Medicare Part D prescription drug plan

The interactive tool on Medicare.gov can help find a Medicare Part D plan that covers your prescriptions. It also helps you compare costs among Medicare Part D and Medicare Advantage plans available to you.

Here are some things to keep in mind when comparing plans:

  • Check the formulary: You’ll want to make sure the medicines you currently take and, importantly, any you think you might need in the future, are covered under each of the plans you’re considering. Talk to your health care providers about what brand-name and generic medicines to look for and any alternatives that may also work in case you can’t find your current medicines on the plans available in your area.

  • Look for plan changes: Formularies change frequently. Your insurer should send you a Notice of Plan Change when the formulary changes. Read this document carefully.

  • Check the pharmacy network: Most Medicare Part D plans negotiate with a network of pharmacies for the lowest cost. Check to see if your pharmacy or an equally convenient one is in the plan’s network. Also, compare prices for using mail order.

If your plan does change, and the change affects the prescription drugs you need, you can switch plans during Medicare's open enrollment period , Oct. 15 to Dec. 7. Changes go into effect on the following Jan. 1.

If you have additional questions about Medicare, visit  Medicare.gov or call 800-MEDICARE (800-633-4227, TTY 877-486-2048).