CMSMLN Matters

MLN: Time-Based E/M Coding

Reference to the CMS rules for selecting an E/M code by total time on the date of the encounter, including the activities that count and prolonged service add-ons.

Primary source

MLN Booklet — Evaluation and Management Services Guide

https://www.cms.gov/outreach-and-education/medicare-learning-network-mln/mlnproducts/downloads/eval-mgmt-serv-guide-icn006764.pdf

Verified May 23, 2026 · This is the authoritative regulator URL. The summary below is a research aid; the linked source controls.

Per the 2021/2023 E/M revisions reflected in the MLN E/M Services Guide, a reporting practitioner may select the E/M level by total time spent on the date of the encounter — not just face-to-face time.

Time activities that count (when performed by the reporting practitioner on the date of the encounter, related to the encounter):

Activities that do not count: time spent by clinical staff, time on separately reportable services, time on a different day, travel, general teaching not specific to the patient.

Prolonged services (99417 for office visits; 99418 for inpatient) capture time above the highest level code (15-minute increments). The thresholds and reportability rules differ for Medicare vs. AMA CPT.

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Last reviewed May 23, 2026 · Citation verified May 23, 2026

Research aid, not legal advice. This summary is an administrative research aid prepared by D3rx. It does not certify compliance, provide legal advice, replace counsel, or guarantee an audit outcome. For authoritative regulatory text follow the primary source link at the top of this page. The practice remains responsible for reviewing, adopting, and maintaining its compliance program.