Why TMS and ECT Need Heavier Prior Authorization

Title: Why TMS and ECT Need Heavier Prior Authorization
SEO Title: TMS & ECT Prior Authorization Requirements
Meta Description: Learn why TMS and ECT claims need intensive prior authorization, physician credentialing, POS checks, and session approval.
Category: Coding & Reimbursement
Author: MCM South Billing Team
Publish Date: TBD — angle: prior authorization intensity

TMS and ECT claims typically require more prior-authorization work than a routine psychotherapy claim. Skipping or rushing that step is one of the more preventable reasons these claims get denied.

TMS means transcranial magnetic stimulation. ECT means electroconvulsive therapy. For billing purposes, TMS generally uses CPT codes 90867–90869, while ECT uses CPT code 90870. Before publishing or submitting claims, verify the current code descriptions and requirements against the AMA CPT code set. Payer policies can also change.

This article covers billing mechanics only. Whether either procedure is appropriate is a clinical decision between the psychiatrist and patient.

TMS Billing Codes (90867–90869)

The TMS code family covers the initial treatment setup and delivery of subsequent treatment services. The exact code depends on the service performed and the current CPT code definition.

Prior authorization is common. A payer may request:

• The diagnosis and relevant clinical documentation.
• A treatment history, which may include previous medication trials or other documented treatment attempts.
• The requested number of TMS sessions.
• The planned frequency and duration of treatment.
• The rendering physician’s credentials and practice location.
• The place of service where treatment will occur.

Do not treat an authorization request as an approval. The authorization should be approved before the first treatment session. Check the authorization number, effective dates, approved units, rendering provider, billing provider, and place of service.

A payer may approve only a defined number of sessions. If the provider expects treatment to continue beyond that number, request additional sessions before the approved units are exhausted. Keep the approval and supporting records with the claim documentation.

For related guidance, see TMS and ECT procedure billing for psychiatric practices.

ECT Billing Code (90870)

CPT 90870 is used for ECT services. Confirm the current CPT descriptor and payer-specific billing rules before filing a claim.

ECT authorization requests can require substantial supporting documentation. A payer may ask for treatment history, the requested course of treatment, the physician’s credentials, and the location where the service will be performed. The approved course may be limited by dates or units.

Place of service matters. The claim must identify where the procedure occurred, such as an office, outpatient hospital, or inpatient setting. The correct place-of-service code depends on the actual setting and the payer’s billing rules. Do not copy the place of service from a prior claim without checking that the current session occurred in the same type of location.

If facility and professional services are billed separately, confirm which entity is billing each service. Check whether the payer requires separate claims, specific provider identifiers, or additional authorization information.

Why These Claims Get Extra Scrutiny

TMS and ECT claims receive closer review than many routine psychotherapy claims for several billing reasons.

Prior authorization is more detailed

Payers often want medical-necessity documentation before they approve these procedures. That request may include prior treatment history, the proposed treatment course, and the number of sessions requested.

Routine psychotherapy claims may also require authorization, but the process is not identical. Never assume that an authorization for evaluation, medication management, or psychotherapy covers TMS or ECT.

The approval may be unit-specific

An authorization can apply to a specific number of sessions, a specific date range, a specific provider, or a specific location. A claim can deny when the billed service falls outside any of those limits.

Place of service affects the claim

The payer compares the billed place of service with the authorized location and the provider’s enrollment information. A mismatch can trigger a denial or a request for records.

These are physician-only procedures

TMS and ECT procedures are physician-only services for billing and performance purposes under the scope described here. Confirm that the performing psychiatrist or other qualified physician meets the payer’s credentialing and enrollment requirements. A prior authorization does not replace credentialing.

The claim is tied to a procedure, not only a therapy session

Payers may compare the procedure code, diagnosis, treatment records, authorization, provider credentials, units, dates, and location. Missing or inconsistent information gives the payer a reason to pause or deny the claim.

MCM South recommends using a pre-submission review for these claims. Verify the authorization, code, units, dates, place of service, provider identifiers, and supporting documentation before the claim goes to the clearinghouse. Our guide to documenting outpatient mental health CPT codes provides broader documentation reminders for behavioral health claims.

Who Can Bill and Perform These Procedures

TMS and ECT require more than a valid CPT code. The performing physician must meet the payer’s credentialing, enrollment, and scope-of-practice requirements. The billing provider and rendering provider also need to be identified correctly on the claim.

Before the first session, confirm:

• The physician is credentialed with the payer for the applicable service.
• The physician’s National Provider Identifier and tax identification information are correct.
• The practice location is enrolled and matches the authorized location.
• The payer recognizes the provider as eligible to bill the procedure.
• Any facility arrangement is documented and billed by the correct entity.

Credentialing and authorization are separate steps. Credentialing confirms that the provider can participate and bill under the payer’s rules. Prior authorization confirms that the payer approved the requested service under its policy. Both should be checked before treatment begins.

This is different from routine psychotherapy billing. Provider type affects which services a payer will recognize. Practices should review payer requirements for psychiatrists, psychologists, therapists, and other behavioral health professionals rather than assuming one provider’s enrollment applies to another. For help with broader psychiatry billing services, use a billing team that understands behavioral health provider rules.

Does TMS or ECT require prior authorization?

Almost always, yes. Both typically require prior authorization documenting medical necessity and treatment history before the payer approves a specific number of sessions. Requirements vary by payer and plan. Verify the policy directly with the insurer and obtain an approval, not merely a tracking number for a submitted request.

Ask the payer to confirm the approved CPT code, units, dates, provider, location, and any required modifiers or claim attachments. Record the representative’s name, reference number, date, and instructions.

FAQ

Does TMS require prior authorization?
Typically, yes. Most payers require supporting documentation before approving a specific number of TMS sessions. Confirm the requirement for the patient’s exact plan.

Does ECT require more prior authorization than TMS?
Often, ECT authorization involves extensive documentation. However, do not assume a fixed hierarchy between procedures. Confirm the specific payer’s policy, documentation list, approved units, and effective dates.

What happens if TMS or ECT treatment starts before authorization is approved?
The claim is at high risk of denial. A request that is pending is not the same as an approval. Confirm approval before the first treatment session and verify that the approved provider and location match the planned service.

Does an authorization guarantee payment?
No. Authorization supports coverage for the approved service, but payment can still depend on eligibility, network status, correct coding, credentialing, place of service, timely filing, and the payer’s claim rules.

Can a psychotherapy authorization be used for TMS or ECT?
Usually not. These procedures have different codes and payer requirements. Request authorization for the specific procedure and confirm the approved units before billing.

The Takeaway

Prior authorization for TMS and ECT is a documentation-heavy process. It is worth getting right before the first session, not treating it as a formality after treatment starts.

MCM South helps psychiatric practices check eligibility, manage authorization details, submit claims, work denials, and track payer policy changes. Our team focuses exclusively on mental and behavioral health billing, so the workflow reflects procedure-specific payer requirements rather than general medical billing assumptions.

Quick Action Checklist

• Confirm prior authorization is approved, not just requested, before the first treatment session.
• Document prior treatment history and include every item the payer requests with the authorization submission.
• Confirm the specific number of approved sessions, effective dates, provider, CPT code, and place of service before scheduling the full course.

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Watch: MCM South Medical Billing Service — YouTube Channel (https://www.youtube.com/@mcmsouthmedicalbillingserv79)

MCM South Medical Billing Service, LLC has specialized in mental and behavioral health billing since 2010. We serve psychotherapists and psychiatrists in Georgia, Massachusetts, Connecticut, Texas, Florida, and New York, with billing experience across all 50 states. Our services include eligibility checks, claims, denial follow-up, credentialing, and payer policy support for solo practitioners and small-to-medium group practices. Our team is bilingual in English and Spanish.

Related topics for a future post:

• Why TMS and ECT Claims Get Denied More Than Psychotherapy Claims
• Eligibility and Benefits Verification
• TMS and ECT Procedure Billing for Psychiatric Practices

Related resources

• CPT and non-E/M code guide
• Mental health parity
• Electronic remittance advice (ERA)
• State and Regional Billing Guides
• Insurance credentialing for therapists and psychiatrists
• Credentialing and network status
• In-network vs. out-of-network credentialing

Ready to hand off the billing? Get a free quote or schedule a consultation with MCM South, a billing service for psychotherapists and psychiatrists.