Time-Based Billing
Method for selecting an E/M level using the total time spent on the date of the encounter.
1 min read · Last reviewed May 23, 2026
At a glance
- Category
- 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
The 2021/2023 AMA E/M rules let you choose time as the basis. The thresholds (e.g., 99214 = 30-39 minutes total time) are published in CMS MLN. Time includes pre-, intra-, and post-encounter work on the date of service.
How it shows up in your practice
Document the total time spent and a brief breakdown of activities (chart review, exam, counseling, documentation). Time and MDM cannot be combined within a single encounter.
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 time-based visits 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.
- CodingE/M CodingEvaluation and Management codes (99202-99499) used to bill office, hospital, and other professional visits.
- CodingProlonged ServicesAdd-on codes used when a visit exceeds the time thresholds of the highest base E/M code.
D3rx is a healthcare-billing and compliance research aid maintained by D3rx Inc. Articles are drafted by an LLM (Anthropic Claude) against primary HHS, OCR, CMS, eCFR, NIST, and state-regulator publications, and reviewed for restraint and source fidelity by the D3rx team.
Reviewer status: a named credentialed reviewer (CHC, CHPC, or healthcare attorney) is being engaged. Until that engagement is finalized, this page does not claim credentialed review.
Related across the archive
- GlossaryE/M CodingEvaluation and Management codes (99202-99499) used to bill office, hospital, and other professional visits.
- 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.
- GlossaryProlonged ServicesAdd-on codes used when a visit exceeds the time thresholds of the highest base E/M code.
- Glossary99214 vs 99215The two most common established-patient office E/M levels; 99214 represents moderate complexity and 99215 high complexity.
- RegulationMLN: 2021 E/M Office Visit Coding RevisionsReference to the 2021 CPT E/M office visit (99202-99215) code revisions: history and exam no longer used for code selection; medical decision making or time controls.
- GlossaryCPT (Current Procedural Terminology)The AMA-maintained code set that describes medical, surgical, and diagnostic services for billing.
- GlossaryCritical Care (99291-99292)CPT codes for evaluation and management of a critically ill or critically injured patient, time-based.
- 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.
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.