Medicare in Oklahoma

Oklahoma was among the first states to ensure access to Medigap plans for people under age 65

At a glance: Medicare in Oklahoma

Medicare enrollment in Oklahoma

As of July 2020, there were 749,954 residents enrolled in coverage through Medicare in Oklahoma.

In most cases, filing for Medicare benefits goes along with turning 65, and people who are already receiving Social Security or Railroad Retirement benefits are automatically enrolled in Medicare when they turn 65.

But people also become eligible for Medicare if they have ALS or kidney failure, or after they’ve been receiving disability benefits for 24 months. 18 percent of Medicare beneficiaries in Oklahoma are eligible due to a disability rather than age. Nationwide, 15 percent of all Medicare beneficiaries are eligible due to disability.

Medicare Advantage in Oklahoma

In most areas of the country, private Medicare Advantage plans are available as an alternative to Original Medicare. People who enroll in Original Medicare get their coverage directly from the federal government, and have access to a nationwide network of providers. But Original Medicare enrollees need supplemental coverage (from an employer-sponsored plan, Medicaid, or privately purchased plans) for for prescription drugs and to reduce and cap out-of-pocket costs.

Original Medicare includes Medicare Parts A and B. Medicare Advantage enrollment includes all of the benefits of Medicare Parts A and B, and Medicare Advantage plans typically have additional benefits, such as integrated Part D prescription drug coverage and extras like dental and vision. But provider networks are limited in Medicare Advantage plans, and out-of-pocket costs are often higher than they would be under Original Medicare plus a Medigap plan. There are pros and cons to either option, and no single solution works for everyone.

Only 18 percent of beneficiaries of Medicare in Oklahoma were enrolled in Medicare Advantage plans as of 2018, compared with an average of 34 percent nationwide. But by mid-2020, enrollment in Medicare Advantage plans in Oklahoma had grown to about a quarter of the state’s total Medicare population. As of July 2020, there were 190,175 enrollees in Medicare Advantage plans in Oklahoma. The other 559,779 enrollees had Original Medicare.

For 2020, the availability of  Medicare Advantage  plans in Oklahoma ranges from just two plans in Beaver, Ellis, Greer, Harmon, and Texas counties, to 30 plans in Tulsa County.

Medicare’s annual election period (October 15 to December 7 each year) allows Medicare beneficiaries the chance to switch between Medicare Advantage and Original Medicare (and add, drop, or switch to a different Medicare Part D prescription plan). People who are already enrolled in Medicare Advantage plans also have the option to switch to a different Advantage plan or to Original Medicare during the Medicare Advantage open enrollment period, which runs from January 1 to March 31.

Medigap in Oklahoma

More than half of Original Medicare beneficiaries have supplemental coverage under an employer-sponsored plan or Medicaid. But for those who don’t, Medigap plans (also known as Medicare supplement plans) will pay some or all of the out-of-pocket costs that Medicare beneficiaries would otherwise have to pay themselves. Original Medicare does not limit out-of-pocket costs, so most enrollees maintain some form of supplemental coverage; Medigap plans are what’s available for people who don’t have access to an employer-sponsored plan (including retiree plans) or Medicaid.

Although Medigap plans are sold by private insurers, the plans are standardized under federal rules. There are ten different plan designs (differentiated by letters, A through N), and the benefits offered by a particular plan (Plan A, Plan F, etc.) are the same regardless of which insurer is selling the plan. So it’s easier to compare Medigap policies than it is to compare other types of health insurance; consumers can base their decision on premiums and less tangible factors like customer service, since the benefits themselves are uniform.

Forty-seven insurers offer Medigap plans in Oklahoma as of 2020. According to an AHIP analysis, there were 203,944 Medicare beneficiaries in Oklahoma who had Medigap coverage as of 2018.

Unlike other private Medicare coverage (Medicare Advantage plans and Medicare Part D plans), there is no annual open enrollment window for Medigap plans. Instead, federal rules give enrollees a one-time six-month window when Medigap coverage is guaranteed-issue. This window starts when a person is at least 65 and enrolled in Medicare Part B (you must be enrolled in both Part A and Part B to buy a Medigap plan).

People who aren’t yet 65 can enroll in Medicare if they’re disabled and have been receiving disability benefits for at least two years, 18 percent of Medicare beneficiaries  in Oklahoma are under age 65. Federal rules do not guarantee access to Medigap plans for people who are under 65, but Oklahoma is among the majority of the states that have implemented rules to ensure that disabled Medicare beneficiaries have at least some access to Medigap plans.

Oklahoma was one of the first states to address this issue, and has guaranteed access to Medigap plans for people under age 65 since 1994. The initial rule just required Medigap insurers to offer at least one plan to applicants under the age of 65. But since 2017, state law has also required insurers to offer that policy without charging a higher premium to disabled enrollees [see OAC 365:10-5-129(d)]. Medigap insurers in Oklahoma have to offer at least one Medigap plan to enrollees under the age of 65, during a six-month open enrollment period that begins when the person is enrolled in Medicare Part B. And insurers cannot charge a premium higher than the lowest available age-based premium that applies to that plan (ie, the rate that would be charged for a 65-year-old enrolling in the plan after gaining eligibility for Medicare due to age).

Almost all of Oklahoma’s Medigap insurers have opted to offer Plan A as their option for enrollees under the age of 65, but as of 2020, United American Insurance offers Plan B, high-deductible Plan F, and high-deductible Plan G to enrollees under age 65, while Reserve National Insurance offers Plan C, Plan F, high-deductible Plan F, Plan G, and Plan N.

People who have Medicare prior to age 65 are granted another six-month Medigap open enrollment period when they turn 65, during which they can select any available plan from any insurer. Many more Medigap options are available to people who are turning 65 than to people below that age, so this is an opportunity for an enrollee to obtain more robust coverage if they prefer it (Plan A, which is the option that most insurers make available to people under age 65 who have Medicare in Oklahoma, is the least comprehensive Medigap plan).

Although the Affordable Care Act eliminated pre-existing condition exclusions in most of the private health insurance market, those rules don’t apply to Medigap plans. Medigap insurers can impose a pre-existing condition waiting period of up to six months, if you didn’t have at least six months of continuous coverage prior to your enrollment. And if you apply for a Medigap plan after your initial enrollment window closes (assuming you aren’t eligible for one of the limited guaranteed-issue rights), the insurer can consider your medical history in determining whether to accept your application, and at what premium.

Oklahoma Medicare Part D

Original Medicare does not provide coverage for outpatient prescription drugs. More than half of Original Medicare beneficiaries have supplemental coverage via an employer-sponsored plan (from a current or former employer or spouse’s employer) or Medicaid, and these plans often include prescription coverage.

But people who are enrolling in Medicare and do not have drug coverage through Medicaid or an employer-sponsored plan need to obtain Medicare Part D prescription drug coverage. Medicare Part D plans can be purchased as a stand-alone plan, or as part of a Medicare Advantage plan with integrated Part D prescription drug coverage.

29 stand-alone Medicare Part D plans in Oklahoma are available in 2020, with premiums that range from about $13 to $138/month.

As of mid-2020, almost half of Oklahoma’s Medicare beneficiaries (346,780 people) had prescription drug coverage under stand-alone Medicare Part D enrollment. Another 169,166 Oklahomans had Medicare Part D prescription drug coverage integrated with their Medicare Advantage plans.

Medicare Part D enrollment is available when a person is first eligible for Medicare, and there is also an annual open enrollment period in the fall (the same window that applies to Medicare Advantage plans), from October 15 to December 7, when beneficiaries can enroll in a Medicare Part D plan or switch to a different plan for the coming year.

Medicare spending in Oklahoma

In 2018, Original Medicare’s average per-beneficiary spending in Oklahoma was $11,115, based on data that were standardized to eliminate regional differences in payment rates, and did not include costs for enrollees in Oklahoma’s Medicare Advantage plans.

Nationwide, average per beneficiary Original Medicare spending was $10,096 per enrollee, so Medicare spending in Oklahoma was about 10 percent higher than average. Oklahoma was one of just five states where average per-beneficiary spending for Original Medicare exceeded $11,000 that year; only Texas, Louisiana, Mississippi, and Florida had higher average per-beneficiary spending than Oklahoma. Per-beneficiary Original Medicare spending was highest in Louisiana, at $11,932, and lowest in Hawaii, at just $6,971.

Medicare in Oklahoma: Resources

Questions about Medicare eligibility in Oklahoma or Medicare enrollment in Oklahoma? You can contact the Oklahoma Senior Health Insurance Counseling Program with questions related to Medicare coverage in Oklahoma.

The Oklahoma Insurance Department maintains a page of resources for people who are eligible for Medicare in Oklahoma.


Louise Norris is an individual health insurance broker who has been writing about health insurance and health reform since 2006. She has written dozens of opinions and educational pieces about the Affordable Care Act for healthinsurance.org. Her state health exchange updates are regularly cited by media who cover health reform and by other health insurance experts.

Find Medicare plans

Helping millions of Americans since 1994.

(Step 1 of 2)

Oklahoma section