Everything you need to know about TMS Prior Authorization: What Your Clinic Submits and How Long It Takes — how it works, what it costs, and how to find a provider who actually knows what they're doing.
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TMS prior authorization is your insurance plan’s approval, given before treatment starts, that it considers TMS medically necessary for you. Your clinic usually submits the request, backed by your diagnosis, depression scores, medication history and a treatment plan. How long a decision takes depends on your plan type and state, and some plans have legal deadlines while others don’t publish one.
Here’s what actually goes into the request, who is responsible for what, and what to do while you wait.
Key takeaways
- Most plans that cover TMS require prior authorization first. Some, like Humana’s commercial plans, list TMS on their preauthorization lists.
- Your clinic normally files the request. You can speed it up by pulling your medication and therapy history ahead of time.
- Federal decision deadlines (72 hours for urgent requests, seven calendar days for standard ones) apply to specific programs, including Medicare Advantage and Medicaid, not to every commercial plan.
- Don’t start treatment until you have the approval in writing, unless your clinic has confirmed in writing that your plan allows it.
- A denial isn’t the end. You can ask for a peer-to-peer review, file an internal appeal, and in many cases request an independent external review.
What prior authorization is
Prior authorization (also called prior auth, pre-authorization or pre-certification) is a review your insurer does before it agrees to pay for a service. For TMS, the reviewer checks your records against the plan’s written medical policy. If you meet it, the plan issues an authorization for a set number of sessions and dates. If you don’t, you get a denial that should say which requirement wasn’t met.
Plans use prior authorization for TMS because it’s a multi-week course with a defined set of criteria. Humana’s commercial preauthorization list (revision dated December 2024) lists the TMS codes together under behavioral health services. TRICARE’s West Region contractor, TriWest, states in its TMS policy that pre-authorization is required. Those are two examples; your plan’s rules are the ones that count.
Not sure which codes the request should name? Our explainer on TMS CPT codes 90867, 90868 and 90869 covers it.
What your clinic submits
Every plan has its own form, but payer policies ask for the same kinds of evidence. Based on the published policies we reviewed from Louisiana Blue, Aetna and Humana’s Louisiana Medicaid policy, a typical packet includes:
| What the reviewer wants | What that usually looks like |
|---|---|
| A confirmed diagnosis | Major depressive disorder, documented by a psychiatrist or qualified clinician, often with a standardized rating scale such as the PHQ-9 |
| Severity | Baseline scores on the same scale the clinic will use during treatment |
| Medication history | Names, doses, start and stop dates, and why each medication was stopped, with a focus on the current episode |
| Psychotherapy history | Some plans ask whether you’ve tried evidence-based therapy |
| Safety screen | Seizure history, implanted metal or devices, other contraindications the policy lists |
| The treatment plan | Device and protocol, requested sessions, the CPT codes the clinic expects to bill |
| Provider credentials | Some plans require a psychiatrist’s referral or a specific type of prescriber |
What counts as enough medication history differs a lot between plans. Some want two medications from different classes, others ask for more. Our qualification checklist is a good place to start.
What you can do to speed it up
The most common delay is missing records, not a slow reviewer. You can help.
- Gather your medication list. Include every antidepressant and add-on you’ve tried in this episode, the dose, and roughly how long you took it. Pharmacy printouts can help document how long you took each one.
- Note why you stopped each one. “No improvement after eight weeks” and “stopped because of severe nausea” are different reasons, and some plans treat them differently.
- List therapy. Type of therapy, how long, and whether it helped.
- Fill out the rating scales honestly. Your baseline PHQ-9 is part of the case. Tracking it also helps once treatment starts; see how to track your PHQ-9 during TMS.
- Ask who owns each step. Does your clinic file it, or does your referring psychiatrist? Get a name and a date for follow-up.
How long does it take?
There’s no single number, and we won’t give you one we can’t source. Here’s what is documented.
The Centers for Medicare & Medicaid Services finalized a rule that sets decision deadlines for certain payers. According to CMS’s announcement, impacted payers must decide expedited requests within 72 hours and standard requests within seven calendar days, with the timeframes beginning primarily in 2026. The payers covered include Medicare Advantage organizations, Medicaid and CHIP fee-for-service programs, and Medicaid and CHIP managed care. Qualified health plan issuers on the federally facilitated exchanges are excluded from those timeframes.
If you have an employer plan or another commercial plan, those federal deadlines may not apply. State laws and plan contracts set the timing, and they vary. Ask your insurer or your plan’s provider portal what the standard review time is for your request.
Two practical points:
- Urgent isn’t a shortcut. Expedited review is for cases where waiting could seriously harm your health. Your clinician has to support that request.
- The clock may not start until the file is complete. A request missing records can be pended while the plan asks for more information.
Don’t start before you’re approved
If your plan requires prior authorization and you start sessions first, the plan can deny those sessions. Whether a plan will review sessions after the fact varies, and plenty won’t. Ask your clinic and your plan, and get the answer in writing. Starting early on the strength of a verbal “it should be fine” is how patients end up with large bills.
Also check what exactly was approved:
- The date range. Authorizations typically run for a window of time.
- The number of sessions. A request for a standard course is not the same as an open-ended approval.
- The codes. Confirm that the codes your clinic expects to bill are listed.
- The location and provider. Approvals are usually tied to a specific provider.
Plans that work differently
- Original Medicare. TMS coverage comes from regional local coverage determinations (LCDs). The LCD text we reviewed (L33398) doesn’t itself set a prior authorization requirement, but confirm with your clinic how they handle Medicare billing. See our Medicare TMS coverage update.
- Medicare Advantage. These plans must follow Medicare’s coverage rules, and they can add their own prior authorization steps. Check your plan’s current list.
- Kaiser Permanente. Because Kaiser is an integrated system, the request is typically handled inside Kaiser rather than between a clinic and a separate insurer. Kaiser Foundation Health Plan of Washington’s published criteria say preauthorization is required for rTMS.
- TRICARE and Medicaid. Both have their own authorization processes and criteria. See our TRICARE page and Medicaid page.
If you’re denied
A denial letter has to state the reason. Read it before you do anything else. Common reasons include missing documentation, a medication history that doesn’t meet the plan’s definition, or the plan calling the treatment not medically necessary for your situation.
Your options, roughly in order:
- Fix the paperwork. If the denial is about missing information, your clinic can resubmit.
- Request a peer-to-peer. Many plans let your clinician talk directly to the plan’s medical reviewer.
- File an internal appeal. The letter lists the deadline. Your clinician can write a letter of medical necessity.
- Ask for external review. On Healthcare.gov, you generally have four months after you receive the denial notice to request an independent external review. Standard reviews are decided within 45 days and expedited reviews within 72 hours or less, depending on urgency. Other plan types follow state or federal rules that differ.
We lay out the full process, with letter tips, in our TMS insurance appeals guide and the insurance denial and appeals page.
What to do next
Start with your insurance card and the member services number. Ask: “Does my plan require prior authorization for TMS, and where can I read the medical policy?” Then find a TMS clinic near you that lists your insurer, and ask the clinic’s insurance coordinator how they handle authorization. If you’re not sure you’d meet the typical criteria, try our candidate quiz first.
Plans update their policies, forms and deadlines. Always check your own plan’s current rules before you rely on anything in this guide.
FAQ
Does TMS always require prior authorization?
Not always, but most plans that cover TMS ask for it. Humana’s commercial list and TriWest’s TRICARE policy are examples that do. Your plan’s current medical policy or member services line will tell you for sure.
Who submits the prior authorization, me or the clinic?
Usually the clinic or the referring psychiatrist. You supply records and sign consents. Ask who is responsible so nothing gets dropped.
How long does TMS prior authorization take?
It depends on the plan. For Medicare Advantage, Medicaid and CHIP, federal rules set decision deadlines of 72 hours for expedited requests and seven calendar days for standard ones, beginning primarily in 2026. Other plans set their own timeframes, so ask yours.
Can I start TMS while my authorization is pending?
Only if your plan allows it and you have that in writing. Otherwise, sessions delivered before approval can be denied, and you may owe the cost.
What if my TMS authorization is denied?
Ask for the written reason, then consider a peer-to-peer review, an internal appeal and an external review. Your clinician can support each step with a letter of medical necessity.
Does an approval guarantee my plan will pay?
It’s a strong sign, but it isn’t a guarantee of payment. Your deductible, copay or coinsurance still apply, and approval is based on the information submitted. Confirm your cost share separately.
