Best Medicare Part D Prescription Drug Plans in 2023

These Medicare Part D plans stand out for member satisfaction, low premiums, high value and $0-copay and $0-deductible options.
Alex Rosenberg
By Alex Rosenberg 
Edited by Dawnielle Robinson-Walker

Many or all of the products featured here are from our partners who compensate us. This may influence which products we write about and where and how the product appears on a page. However, this does not influence our evaluations. Our opinions are our own. Here is a list of our partners and here's how we make money.

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, 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, buy a Part D plan if you have a Medicare Supplement Insurance plan that doesn’t cover prescription drugs.

Best Medicare Part D plans for 2023

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 2023 stand out:

Best for member satisfaction: AARP/UnitedHealthcare Medicare Part D

Average Medicare Part D star rating, weighted by enrollment: 3.21 stars.

Top quality measures that outperformed the national average:

  • Call center foreign language interpreter and TTY, or teletypewriter, availability.

  • Medicare plan finder price accuracy.

  • Few members choosing to leave the plan.

Standout feature: AARP/UnitedHealthcare Medicare Part D plans get few complaints, have few members that choose to leave and outperform several competitors on surveys about members’ experience with the plan.

Company overview: More than 4 million Medicare beneficiaries have 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, especially for measures of member satisfaction. Pricing for the highest-coverage AARP/UnitedHealthcare Part D plan can get expensive, however, and the plans’ ratings for helping members with their medications aren't as strong.

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.

  • You'll pay copays rather than coinsurance for drugs on Tiers 1-3 in most UHC plans.

Cons:

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

  • Only the most expensive AARP/UHC plan has any $0-copay options.

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

Best for low premiums: Aetna Medicare Part D

Average Medicare Part D star rating, weighted by enrollment: 3.5 stars.

Top quality measures that outperformed the national average:

  • Drug plan quality improvement.

  • Call center foreign language interpreter and TTY availability.

  • Few complaints about the drug plan.

Standout feature: Aetna offers the least expensive stand-alone Medicare Part D plan, 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.

Aetna's Part D premiums are among the lowest on the market, but you’ll need to look carefully at the copay and coinsurance requirements to see whether you’ll save money overall.

Pros:

  • Aetna’s SilverScript SmartSaver 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.

  • Aetna significantly outperformed the national average on CMS’ measure of year-over-year quality improvement.

Cons:

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

  • Aetna underperformed on quality measures related to helping members get and properly take their medications.

  • The SilverScript Choice plan used to have no deductible for Tier 1 and Tier 2 drugs, but now the deductible applies to all covered drugs.

» MORE: Read our review of Aetna Medicare Part D insurance

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

Average Medicare Part D star rating, weighted by enrollment: 3.52 stars.

Top quality measures that outperformed the national average:

  • Medicare plan finder price accuracy.

  • Drug plan quality improvement.

  • Members’ rating of the drug 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.

Among the five largest Medicare Part D companies, Cigna has the highest average summary star rating, weighted by enrollment.

Pros:

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

  • 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, high cholesterol 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.

» MORE: Read our review of Cigna Medicare Part D insurance

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

Average Medicare Part D star rating, weighted by enrollment: 3.02 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.

  • Drug plan quality improvement.

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 plans get below-average star ratings, weighted by enrollment, from CMS. Its plans fall short on three-quarters 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 gets above-average ratings for its program to help members manage their medications — a category where many competitors struggle.

Cons:

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

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

» MORE: Read our review of Humana Medicare Part D insurance

Find the right Medicare Part D prescription drug plan

The interactive tool on Medicare.gov can help you 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 that 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).
Get more smart money moves – straight to your inbox
Sign up and we’ll send you Nerdy articles about the money topics that matter most to you along with other ways to help you get more from your money.