E/M Coding
Evaluation and Management Coding
Evaluation and Management codes (99202-99499) used to bill office, hospital, and other professional visits.
1 min read · Last reviewed May 23, 2026
At a glance
- Category
- Coding
- Acronym for
- Evaluation and Management Coding
- Primary sources
- 2
- Workspace handoff
- revenue audit →
Where this comes up
Coders meet this term inside the chart at the moment of code selection — picking the E/M level, attaching the right modifier, defending the procedure code against an NCCI edit, or answering an auditor who pulled the encounter for a payer-initiated review.
Full definition
What it is in practice
CMS follows the 2021 (office) / 2023 (other sites) AMA revisions that base E/M selection on either medical decision making or total time. Time thresholds and MDM elements are specific to each code; pick one method per encounter.
How it shows up in your practice
Pick MDM or time and apply it consistently. Document the elements that justify the level. Random level-4 / level-5 patterns without supporting documentation are an audit magnet.
Sources
- CMS — Evaluation and Management (E/M) Services Guidehttps://www.cms.gov/outreach-and-education/medicare-learning-network-mln/mlnproducts/downloads/eval-mgmt-serv-guide-icn006764.pdf
- AMA — 2021 / 2023 E/M Documentation Guidelineshttps://www.ama-assn.org/practice-management/cpt/cpt-evaluation-and-management
Audit your E/M distribution in Revenue Audit
Open revenue audit →Related terms
- CodingMedical Decision Making (MDM)One of two methods (with time) for selecting an E/M level, based on the number and complexity of problems, the amount and complexity of data reviewed, and the risk of complications.
- CodingTime-Based BillingMethod for selecting an E/M level using the total time spent on the date of the encounter.
- Coding99214 vs 99215The two most common established-patient office E/M levels; 99214 represents moderate complexity and 99215 high complexity.
- BillingModifier 25CPT modifier indicating that a significant, separately identifiable E/M service was performed by the same provider on the same day as another procedure or service.
- BillingCPT (Current Procedural Terminology)The AMA-maintained code set that describes medical, surgical, and diagnostic services for billing.
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Related across the archive
- Glossary99214 vs 99215The two most common established-patient office E/M levels; 99214 represents moderate complexity and 99215 high complexity.
- GlossaryMedical Decision Making (MDM)One of two methods (with time) for selecting an E/M level, based on the number and complexity of problems, the amount and complexity of data reviewed, and the risk of complications.
- GlossaryTime-Based BillingMethod for selecting an E/M level using the total time spent on the date of the encounter.
- GlossaryCPT (Current Procedural Terminology)The AMA-maintained code set that describes medical, surgical, and diagnostic services for billing.
- Billing99214 vs 99215: When to Bill Each CodeLearn the difference between 99214 and 99215: when each applies, what documentation you need, and the $40/visit revenue impact.
- GlossaryModifier 25CPT modifier indicating that a significant, separately identifiable E/M service was performed by the same provider on the same day as another procedure or service.
- BillingModifier 25: When to Use It and Common MistakesWhen to use modifier -25, when to skip it, and the common mistakes that trigger audits and denials.
- RegulationMLN: Time-Based E/M CodingReference 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.
This glossary entry is a research aid for billing and compliance staff. It does not provide legal, medical, or financial advice and does not replace counsel. References cited link to primary sources at HHS, OCR, CMS, eCFR, NIST, and the relevant payer or industry body.