Medicare's WISeR Model: Prior Authorization, Spending & Key Findings for 2026

On January 1 2026 the Center for Medicare & Medicaid Innovation (CMMI) launched the Wasteful and Inappropriate Service Reduction (WISeR) Model, adding new prior‑authorization requirements to traditional Medicare for a selected set of services in six states. The model tests artificial‑intelligence‑driven reviews over a six‑year trial and marks the first large‑scale use of prior authorization in fee‑for‑service Medicare.

What the WISeR Model Introduces

The WISeR Model requires prior authorization for skin substitutes, orthopedic pain‑management procedures (including cervical fusion and epidural steroid injections), electrical nerve‑stimulator implants, incontinence control devices, and services for diagnosing and treating impotence. Two services—deep brain stimulation and percutaneous image‑guided lumbar decompression—have been delayed and will be added later.

CMS has partnered with a private health‑technology company in each of the six states (Arizona, New Jersey, Ohio, Oklahoma, Texas, Washington) to conduct the AI‑based reviews. Vendors will share in any savings generated from denied services, but must obtain a clinician’s second opinion before a denial is finalized.

Did You Know? Prior authorization is routine in Medicare Advantage and private insurance, yet it has been rare in traditional Medicare until the WISeR Model’s launch.

Why the Model Matters

Nearly seven in ten adults with health insurance (69 %) consider prior authorization a burden, and more than a third (34 %) rank it as their single biggest obstacle to care. WISEr services accounted for 5.3 % ($12.3 billion) of all Part B spending in traditional Medicare in 2024, up from 1.1 % ($2.4 billion) in 2019.

Skin substitutes dominate this category, representing 83 % ($10.3 billion) of WISeR spending in 2024. Their average price per service rose from $2,300 in 2019 to $21,200 in 2024—an 820 % increase—while utilization grew modestly.

In 2024, 1.1 million traditional‑Medicare beneficiaries (3.2 % of the programme) received at least one WISeR service. Orthopedic pain‑management procedures were the most common (86 % of WISeR users), whereas skin substitutes were used by only 9.3 %.

Expert Insight: While the WISeR Model could trim wasteful use, its first‑year impact is likely modest because the targeted services touch a limited beneficiary pool and most spending growth stems from price hikes—not volume—that prior authorization cannot directly curb. The simultaneous nationwide payment reform for skin substitutes, projected to cut spending on that category by roughly 90 %, may outweigh any savings from the model’s use restrictions.

Potential Impact in the First Year

Because WISeR services comprise a small slice of total Part B spending and are used by relatively few beneficiaries, the model’s early fiscal effect is expected to be limited. The bulk of spending growth has been driven by skin substitutes, whose cost trajectory will be sharply altered by the new fixed‑rate reimbursement of $127.28 per square centimeter that began on January 1 2026.

Providers outside the six pilot states will not face the new requirements, and even within the states only about 20 % of WISeR users (≈207,500 beneficiaries) will be subject to the authorization process.

State‑by‑State Variation

Per‑capita WISeR spending in 2024 ranged from $202 in Ohio to $748 in Oklahoma, compared with a national average of $371. Much of this variation reflects differences in skin‑substitute use and price, which ranged from $143 per beneficiary in Ohio to $674 in Oklahoma.

Utilization of WISeR services also varied, from 24 per 1,000 beneficiaries in Washington to 43 per 1,000 in Arizona, versus 32 per 1,000 nationwide.

Looking Ahead

The model could be expanded to additional services and states, potentially increasing its reach over time. Safeguards such as mandatory clinician second opinions and audits aim to protect beneficiaries from undue delays or denials, and providers with high approval rates may earn “gold‑card” exemptions.

Policymakers have voiced concerns that the vendor‑payment structure—rewarding savings tied to denied services—might incentivize excessive denials. As the model matures, CMS will need to balance waste reduction with access, monitor administrative burdens, and decide whether broader adoption is warranted.

Frequently Asked Questions

When did the WISeR model begin?

The WISeR Model launched on January 1 2026.

Which services are subject to prior authorization under WISeR?

Skin substitutes, orthopedic pain‑management procedures (such as cervical fusion and epidural steroid injections), electrical nerve‑stimulator implants, incontinence control devices, and services for diagnosing and treating impotence are included. Two services—deep brain stimulation and percutaneous image‑guided lumbar decompression—have been delayed.

How much of Medicare Part B spending do WISeR services represent?

In 2024 WISeR services accounted for 5.3 % of Part B spending in traditional Medicare, roughly $12.3 billion, up from 1.1 % ($2.4 billion) in 2019.

What do you think could be the biggest challenge for providers as the WISeR model rolls out?

Medicare’s WISeR Model: Prior Authorization, Spending & Key Findings for 2026