Medicare Advantage Therapy Rules: What Carries Over

Medicare Advantage plans must cover everything Original Medicare covers, but “cover” and “process a claim” are not the same thing, and confusing them is where billing leads get burned. The legal floor sits at 42 CFR 422.101, as amended by CMS-4201-F: an MA organization must cover all Part A and Part B benefits, follow national and local coverage determinations, and apply the same “reasonable and necessary” medical necessity standard Original Medicare uses. What a plan is free to add is separate: prior authorization programs, network rules, and supplemental benefits like routine chiropractic care.

Two sets of numbers matter for a practice with mixed-payer patients. MA plans are not required to replicate the KX modifier threshold or targeted medical review, both Part B claims-processing tools, not coverage rules. On process, federal rules cap standard decisions on items that require prior authorization at 7 calendar days (down from 14, effective January 1, 2026) and expedited decisions at 72 hours, guarantee a 90-day transition period when a patient switches plans mid-treatment, and require a specific denial reason. Annual enrollment runs October 15 through December 7 for coverage starting the next January 1, and a plan-level appeal moves on a 60-day filing clock instead of Original Medicare’s 120-day redetermination window.

A patient’s plan, network status, and authorization posture can all change on January 1 without anything in the chart flagging it. Current as of September 2026.

What does Medicare Advantage have to cover for outpatient therapy?

An MA organization must cover, arrange, or pay for “all services that are covered by Part A and Part B of Medicare” (42 CFR 422.101(a)), follow national and local coverage determinations, apply the “reasonable and necessary” medical necessity test at (c)(1)(i)(B), and, per (c)(1)(i)(A), “may not deny coverage for basic benefits based on coverage criteria not specified in paragraph (b) or (c).”

Plans get one narrow lane to add their own criteria, only when Medicare criteria are “not fully established” (422.101(b)(6)), and only with public posting of the criteria and evidence. This came from CMS-4201-F, effective June 5, 2023 for coverage beginning January 1, 2024 (Federal Register), which told plans to “look beyond the labels of ‘payment rule’ or ‘coverage rule’” and required a Utilization Management Committee reviewing policies annually against Original Medicare’s decisions (CMS fact sheet). The older Medicare Managed Care Manual, Chapter 4 (Rev. 121, 2016) says it plainer: plans “may not impose limitations, waiting periods or exclusions from coverage due to pre-existing conditions that are not present in original Medicare,” and a plan offering extra coverage “may not limit the original Medicare coverage.” Its therapy-cap section predates the 2018 cap repeal and only cross-references the Claims Processing Manual. A plan can add supplemental benefits, like routine chiropractic, only if they meet 42 CFR 422.100(c)(2)(ii), which requires, among other listed purposes, that they “diagnose, prevent, or treat an illness or injury” or “compensate for physical impairments.”

Which Original Medicare therapy rules carry over to Medicare Advantage?

The regulation never says “physical therapy.” It binds MA to categories: coverage criteria, medical necessity, and the benefit’s own definition. Because 422.101(b)(2) ties MA coverage to “criteria for determining whether an item or service is a benefit available under Traditional Medicare,” anything defining the benefit travels with it: the written plan of treatment at 42 CFR 410.61, established before treatment and prescribing “type, amount, frequency, and duration”; and the Jimmo maintenance standard, that skilled therapy can be necessary to maintain function without improvement (Benefit Policy Manual Ch. 15, §220.2(D)). CMS’s Jimmo guidance does not address MA; the tie runs through 422.101(c)(1)(i)(B)’s reasonable-and-necessary test, so a plan denying maintenance therapy solely for lack of improvement is applying a criterion Original Medicare does not use (see our Jimmo guide).

Certification and 90-day recertification are a Part B payment condition, not a benefit definition (42 CFR 424.24(c)). No MA rule restates it, but CMS’s expectation that plans consult the Benefit Policy Manual makes it reasonable to treat the timing as carrying over; verify the plan’s own manual (see our plan of care and certification and documentation requirements guides).

Part B claims-processing and payment mechanics do not carry over automatically. Contracted rates, CQ/CO, and MPPR are mechanics a plan can replicate by contract, but nothing in 42 CFR Part 422 requires it. Non-contract providers must accept as payment in full “the amounts that the provider could collect if the beneficiary were enrolled in original Medicare” (42 CFR 422.214(a)(1)), pulling that math back in for out-of-network claims (see our CQ/CO and MPPR guides).

Does Medicare Advantage follow the KX modifier threshold?

Not by federal requirement. The KX modifier threshold is a Part B claims-processing mechanism: once a beneficiary’s incurred therapy expenses cross a set dollar amount, each claim line above it must carry the KX modifier “as a confirmation that services are medically necessary as justified by appropriate documentation in the medical record.” The 2018 Bipartisan Budget Act “repeals application of the Medicare outpatient therapy caps but retains the former cap amounts as a threshold,” which Medicare contractors apply and the Common Working File tracks (Claims Processing Manual, Ch. 5, §§10.2–10.3). The CY 2026 threshold is $2,480 for PT and SLP combined, and a separate $2,480 for OT (CMS Transmittal R13437CP, issued October 30, 2025). Nothing in 42 CFR Part 422 requires an MA plan to apply it, and the Managed Care Manual’s therapy-cap section predates the 2018 repeal and does not instruct plans to append KX. Whether a plan wants KX on lines above $2,480 is a question for that plan’s billing guide or provider manual, not a coverage rule.

Track accrual for every Medicare beneficiary regardless of payer. A patient can move to Original Medicare on January 1 or during the MA Open Enrollment Period through March 31, where the Common Working File starts a fresh calendar-year accrual; MA claims are not tracked there. A non-contract MA claim is also paid at the Original Medicare amount, so that math still determines what an out-of-network plan owes (see our KX modifier threshold guide).

What are the federal rules on Medicare Advantage prior authorization for therapy?

Prior authorization is where MA plans add the most, and where federal limits have tightened fastest. An organization determination must be decided within set timeframes (42 CFR 422.568(b)(1); 42 CFR 422.572(a)(1)). Any treating provider can request a standard determination; expedited requests come from the enrollee or “a physician (regardless of whether the physician is affiliated with the MA organization),” and an adverse medical necessity determination must first be reviewed by “a physician or other appropriate health care professional” with expertise in the service at issue (42 CFR 422.566(c), (d)).

CMS-0057-F, the interoperability and prior authorization final rule, added the specific-denial-reason, API, and public-reporting requirements below across MA organizations, Medicaid and CHIP programs, and qualified health plans on the federal exchanges (CMS fact sheet; rule page; 42 CFR 422.122). Posted plan-level metrics let you check a contract’s approval, denial, and turnaround numbers before deciding whether to appeal.

Approval duration and transition protection come from 42 CFR 422.112(b)(8): approval “must be valid for as long as medically necessary,” and coordinated care plans must provide “a minimum 90-day transition period for any active course(s) of treatment when an enrollee has enrolled in an MA plan after starting a course of treatment, even if the service is furnished by an out-of-network provider.” That rule blocks reauthorization and disruption; it does not set the out-of-network payment rate (contract or 422.214).

See our UnitedHealthcare prior authorization guide for one plan’s program layered on top of these federal floors.

What did OIG find about Medicare Advantage denials in 2026?

Two OIG reports published in June 2026 got wide attention, and neither is about outpatient therapy. Both examined post-acute admissions, LTCH, IRF, and SNF, using June 2024 prior authorization data from 19 MA organizations; neither reviewed outpatient therapy claims, so do not read their percentages onto outpatient therapy.

The first, issued June 8, 2026, found the three largest MA organizations denied LTCH and IRF requests “at higher rates than most of their peers in June 2024,” and on appeal “MAOs collectively overturned 36 percent of LTCH denials and 43 percent of IRF denials” (OIG OEI-09-24-00330). The second, same day, found MA organizations “collectively denied 12 percent of requests for SNF admission,” enrollees “appealed 18 percent of SNF denials,” and “MAOs overturned 95 percent in favor of the enrollee” on appeal (OIG OEI-09-24-00331).

The lesson that transfers is procedural, not statistical: in the SNF report, only 18 percent of denials were appealed, and 95 percent of those appeals succeeded. The same organization determination and reconsideration mechanics apply to an outpatient therapy denial as to the post-acute denials OIG studied, so a denial is the start of a process, not the end of one.

What changes for outpatient therapy on January 1?

Three calendars converge on January 1. The Annual Coordinated Election Period (AEP) runs “October 15 through December 7,” letting a beneficiary move from Original Medicare to an MA plan, between MA plans, or back to Original Medicare, effective the next January 1 (42 CFR 422.62(a)(2); medicare.gov). Plans must notify enrollees of January 1 changes “at least 15 days before” AEP begins, meaning by September 30 (42 CFR 422.111(d)(2)), and a plan discontinued in an enrollee’s area triggers a special election period at any time (42 CFR 422.62(b)(1)).

January 1 is not the only reset. The MA Open Enrollment Period runs January 1 through March 31, letting an enrollee switch MA plans or return to Original Medicare once (42 CFR 422.62(a)(3)(i)), so recheck eligibility at each visit through the quarter. A patient who dropped a Medigap policy to join a first MA plan, or who joined an MA plan at 65, can leave it within 12 months and return to Original Medicare with “guaranteed issue” Medigap rights (42 CFR 422.62(b)(8) and (c)). A mid-treatment switch still gets 90-day transition protection, including out-of-network, so an active plan of care is not reauthorized from scratch. None of this depends on which insurer is involved; the task is re-verification, not prediction.

For a patient landing on Original Medicare, the therapy rules flip back: no prior authorization, but the KX threshold, targeted medical review, CQ/CO, and MPPR all apply, and the 20 percent coinsurance is the patient’s unless a Medigap policy picks it up. “You can only buy Medigap if you have Original Medicare” (medicare.gov). Plan G covers 100 percent of the Part B coinsurance; Plan N “pays 100% of the costs of Part B coinsurance” but allows “a copayment of up to $20 for some office visits,” and no Medigap plan sold today covers the Part B deductible (medicare.gov plan comparison). Collect the deductible either way.

How do Medicare Advantage appeals differ from Original Medicare appeals?

Both systems end in federal court, but the names, clocks, and starting point differ. MA begins with an organization determination, defined to include a plan’s “refusal, pre- or post-service … to provide or pay for services” and “reduction, or premature discontinuation, of a previously authorized ongoing course of treatment” (42 CFR 422.566(b)). A treating physician “acting on the enrollee’s behalf” can request the reconsideration that follows, and an upheld denial is forwarded automatically to CMS’s independent review entity (42 CFR 422.582; 42 CFR 422.590; CMS appeals page).

Provider standing depends on contract status. A contract provider’s payment dispute runs through the contract, not a Subpart M appeal, once the enrollee owes nothing further; a non-contract provider needs a Waiver of Liability to appeal (Parts C & D Appeals Guidance, effective July 6, 2026). A pre-service denial is the enrollee’s appeal, one a treating physician can file directly.

Original Medicare has no pre-service prior authorization for outpatient therapy, so its appeals run post-payment on a longer clock: a MAC redetermination (42 CFR 405.942(a); 42 CFR 405.950(a)), then a Qualified Independent Contractor reconsideration (42 CFR 405.962(a); CMS page).

Tracking where a patient sits against the KX threshold gets harder, not easier, once that patient moves between Medicare Advantage and Original Medicare mid-year. PrismEHR tracks accrued therapy dollars per beneficiary against the KX threshold, and lets organizations define their own billing rules, including minute and unit restrictions, enforced at documentation and reinforced again at claim creation. It serves PT, chiropractic, orthopedic, wellness, and primary care organizations billing this payer mix every January. See the KX modifier threshold guide, and how PrismEHR fits physical therapy practices.