Two clocks, one visit: splitting E/M time from therapy time

Why the E/M level must be chosen by MDM, not time, when you add a psychotherapy code

Since the 2021 overhaul of the office and outpatient E/M codes, a visit's level is set by either the total medical decision making (MDM) documented or the total time spent on the date of the encounter — whichever the prescriber elects 1Ref 1Centers for Medicare & Medicaid Services (2023).Evaluation and Management Services Guide.Supports that E/M office-visit levels are selected by MDM or total time under the 2021+ framework.. That flexibility disappears the moment a psychotherapy add-on code is also reported for the same date: the E/M level must be selected by MDM only, because the time spent on the psychotherapy portion is already being counted toward the add-on code, and counting it again toward E/M would double-bill the same minutes under two different codes 2Ref 2American Medical Association (2023).CPT evaluation and management (E/M) revisions.Supports the mechanics of the 2021 E/M revisions underlying the MDM-versus-time framework the add-on carve-out interacts with..

This is the rule the whole two-clock discipline exists to enforce. Get it backwards — select the E/M level by total time on an add-on day — and the claim is vulnerable on audit even if the documented minutes are accurate, because the same minutes were used to justify two separate payments.

The add-on codes: 90833, 90836, 90838

add-on code 90833 (about 30 minutes), 90836 (about 45 minutes), and 90838 (about 60 minutes) each report psychotherapy performed alongside an E/M service on the same date, by the same prescriber — none of the three is ever billed alone, only appended to a primary E/M code 3Ref 3APA Services, Inc. (2025).Psychotherapy Codes for Psychologists.Supports the definition and time bands of the add-on codes 90833/90836/90838 and their pairing with a primary E/M code.. The add-on's time band covers the psychotherapy work specifically: the portion of the visit spent on process-oriented conversation, technique, or intervention distinct from the medical evaluation and management the E/M code already covers.

Which add-on to report is a function of how many minutes the therapy portion actually ran, timed on its own — not a fraction of the total visit length, and not an estimate backed into from the E/M level already chosen.

Two clocks: what each one records

Keep two separate time records for the same date of service: the E/M encounter's own start and stop times (supporting the note even though time isn't what selects the E/M level here) and the psychotherapy add-on's start and stop times, which is what actually drives which add-on code applies. The two clocks should not overlap in the note — a reviewer reading the documentation should be able to see where the medical evaluation ended and the therapy segment began, even within a single continuous visit.

A workable pattern: document the MDM elements — problem addressed, data reviewed, risk — as their own paragraph, then a separate paragraph opening with the therapy segment's start time, its content, and its stop time. The two paragraphs together should account for the full visit length without double-counting any minute toward both services.

Writing the note so the two services don't blur together

A note that blends E/M and therapy content into one undifferentiated paragraph is the single most common reason an add-on claim gets questioned, because the reviewer cannot tell how the add-on's time was isolated from the visit as a whole. Structure the note so each service's content maps cleanly to its own code, even when the visit felt seamless to you and the client.

A structure that holds up on review: - Chief complaint / interval history — brief, feeds MDM. - MDM summary — problem(s) addressed, data reviewed, risk assessed; this justifies the E/M level. - Psychotherapy segment — start time, modality or technique used, content addressed, stop time; this justifies the add-on code. - Plan — medication changes and therapy plan, each attributed to the service that generated it.

Signature, attestation, and what an auditor looks for

Medicare requires every service to carry a handwritten or valid electronic signature authenticating that the documented work was performed as billed, and an unsigned or ambiguously authenticated note can be treated on review as if the service wasn't rendered at all 4Ref 4Centers for Medicare & Medicaid Services (2023).Complying with Medicare Signature Requirements.Supports the signature and authentication requirement that applies to the combined E/M-plus-add-on note.. On a split E/M-plus-add-on note, the signature authenticates both services at once — which is exactly why the note needs to make clear, on its face, that two distinct, appropriately timed services occurred rather than one visit stretched across two codes.

An auditor reviewing this pattern is checking one thing specifically: whether the E/M level would still be supportable by MDM alone with the psychotherapy add-on's minutes removed entirely from consideration. If the note only makes sense as one blended visit, that is the signal the add-on wasn't actually a separately identifiable service.

Records retention and the psychotherapy-notes split

The therapy segment's content may qualify for the same heightened protection HIPAA gives psychotherapy notes — kept separate from the rest of the medical record, with patient authorization required for most disclosures — while the MDM and medication-management content stays in the general chart a covered entity discloses more routinely for treatment, payment, and operations 5Ref 5HHS Office for Civil Rights (2026).Does HIPAA provide extra protections for mental health information compared with other health information?.Supports the two-tier records claim distinguishing heightened-protection psychotherapy notes from the general medical record.. Decide at the point of documentation which segment's detail belongs in which file; retrofitting the split after the fact is far harder than keeping it clean from the start.

Retention guidance commonly runs several years past the last date of service for adult records and longer for minors, with the specific state's own retention statute always controlling over any general guideline 6Ref 6American Psychological Association (2007).Record Keeping Guidelines.Supports the records-retention norm, paired with the reminder that the reader's own state rule controls.. Calendar the state rule, not the norm, as the actual retention floor for this two-service record.

Common mistakes that trigger a down-code or denial

Most add-on denials and downcodes trace to one of a handful of patterns: