What Is E/M Coding? The Complete Guide for Healthcare Providers

E/M stands for Evaluation and Management — the category of CPT (Current Procedural Terminology) codes that physicians, nurse practitioners, and physician assistants use to bill for patient encounters where a clinical evaluation is performed and a management plan is established or continued. E/M codes are the most frequently billed codes in American medicine, covering office visits, emergency department encounters, hospital admissions, telehealth appointments, and nursing facility care. Over 500 million E/M claims are submitted to Medicare each year, making E/M coding the single largest driver of physician revenue.

The E/M code framework was created by the American Medical Association (AMA) and is maintained as part of the CPT code set, which the AMA has published annually since 1966. E/M codes were first introduced as a distinct category in the 1992 CPT code set, establishing the evaluation-and-management framework that replaced earlier “visit codes.” The Centers for Medicare & Medicaid Services (CMS) adopted the AMA’s E/M framework for Medicare reimbursement, and commercial payers followed. The most recent major revision — the AMA 2021 guidelines — eliminated the history and physical exam documentation requirements for office visits and introduced Medical Decision Making (MDM) complexity and total encounter time as the sole determinants of code level.

The E/M Code Families

E/M codes are organized into families based on the clinical setting where the encounter takes place. Each family has its own code range, documentation requirements, and reimbursement rates. The most commonly billed E/M family is office and outpatient visits (99202–99215), but physicians across all specialties use codes from multiple families depending on their practice setting.

Office and Outpatient Visits (99202–99215)

This is the highest-volume E/M code family, used for clinic visits, primary care, and most specialist office encounters. New patient visits use codes 99202–99205 and established patient visits use 99212–99215. Under the AMA 2021 guidelines, these codes are selected based on Medical Decision Making (MDM) complexity or total encounter time. Code 99211 remains for established patient nurse-only visits that do not require physician presence.

Emergency Department Visits (99281–99285)

ED codes use a five-level system based on presenting problem severity, evaluation complexity, and treatment urgency. Unlike office visits, ED codes have not been updated to the 2021 MDM-only model — they still incorporate history and exam elements in many payer guidelines. ED visits do not distinguish between new and established patients.

Hospital Inpatient and Observation (99221–99236)

Inpatient codes cover initial hospital admissions (99221–99223), subsequent hospital visits (99231–99233), observation care (99217–99220), and same-day admit-and-discharge encounters (99234–99236). CMS updated inpatient and observation E/M codes effective January 1, 2024, collapsing formerly separate observation and inpatient code sets into unified families.

Consultations (99241–99255)

Consultation codes are used when a physician provides an opinion at the request of another provider. Outpatient consultations use 99241–99245 and inpatient consultations use 99251–99255. Note: Medicare does not recognize consultation codes and requires providers to bill the appropriate new or established patient visit code instead. Most commercial payers still accept consultation codes.

Telehealth Visits

Synchronous (real-time audio-video) telehealth visits use the same office visit codes (99202–99215) with modifier –95 or place of service code 02. The same MDM and time-based selection rules apply. Audio-only telephone visits use separate codes (99441–99443). CMS made expanded telehealth E/M billing flexibilities permanent following the COVID-19 public health emergency.

Other E/M Families

Critical Care (99291–99292): Time-based codes for critically ill patients requiring constant physician attendance. First 30–74 minutes = 99291, each additional 30 minutes = 99292.
Nursing Facility (99304–99310): Initial (99304–99306) and subsequent (99307–99310) skilled nursing facility visits.
Home or Residence Services (99341–99350): In-home visits for new and established patients.
Prolonged Services (99354–99357): Add-on codes for encounters exceeding the time threshold of the highest-level E/M code.

E/M Code Reimbursement Rates (2024 Medicare National Averages)

The financial difference between E/M code levels is substantial. Billing the correct code — rather than defaulting to a lower level — directly impacts practice revenue. The following table shows 2024 Medicare national average reimbursement rates for office and outpatient E/M codes. Commercial payer rates are typically 110–150% of Medicare.

Code	Patient Type	MDM Level	Medicare Avg
99211	Established	N/A (nurse visit)	$25
99212	Established	Straightforward	$76
99213	Established	Low	$111
99214	Established	Moderate	$167
99215	Established	High	$224
99202	New	Straightforward	$93
99203	New	Low	$148
99204	New	Moderate	$210
99205	New	High	$282

The difference between the lowest and highest established patient codes is $148 per encounter ($76 for 99212 vs $224 for 99215). For new patients, the spread is even larger: $93 for 99202 vs $282 for 99205 — a $189 difference per visit. See the full reference with time thresholds in our E/M Code Levels Chart 2026.

How E/M Codes Are Selected: MDM vs Time

Before the AMA 2021 guidelines, office visit E/M codes were selected based on three documentation “pillars”: history, physical examination, and medical decision making. Physicians were required to document specific numbers of history-of-present-illness elements, review-of-systems entries, and exam bullet points — a system widely criticized for encouraging checkbox documentation over clinical reasoning.

The 2021 overhaul simplified code selection to two methods. Physicians use whichever yields the higher code:

Method 1: Medical Decision Making (MDM)

MDM evaluates three elements: (1) the number and complexity of problems addressed, (2) the amount and complexity of data reviewed or ordered, and (3) the risk of complications, morbidity, or mortality. The physician scores each element independently, then applies the 2-of-3 rule — two of three elements must meet or exceed the target level. MDM produces four complexity levels: straightforward, low, moderate, and high. For a deep dive on scoring each element, see our complete guide to Medical Decision Making in E/M Coding.

Method 2: Total Encounter Time

Physicians may also select E/M codes based on the total time spent on the encounter on the date of service. This includes face-to-face time, chart review, care coordination, order placement, documentation, and communication with the patient’s care team. Time-based coding is particularly advantageous for care coordination-heavy visits where MDM complexity may be low but time investment is high.

Code (Established)	Code (New)	MDM Level	Total Time
99212	99202	Straightforward	10–19 min (est) / 15–29 min (new)
99213	99203	Low	20–29 min (est) / 30–44 min (new)
99214	99204	Moderate	30–39 min (est) / 45–59 min (new)
99215	99205	High	40–54 min (est) / 60–74 min (new)

Use our E/M Calculator to practice scoring encounters using both methods, or paste a clinical note into the AI Analyzer to get dual codes (MDM and time) automatically.

A Brief History of E/M Coding

Understanding where E/M coding comes from helps explain why the system works the way it does today:

1966: The AMA publishes the first edition of CPT, establishing standardized medical procedure codes.
1992: E/M codes are introduced as a distinct CPT category, replacing generic “visit” codes. The original framework requires documentation of history, exam, and MDM to select code levels.
1995 & 1997: CMS publishes two sets of documentation guidelines (the “1995 guidelines” and “1997 guidelines”) specifying how history, exam, and MDM should be documented. Physicians may use either set — both remain valid for non-office E/M codes today.
2019: The AMA announces a major E/M revision effective 2021, focused on reducing documentation burden.
2021 (January 1): The AMA 2021 guidelines take effect for office and outpatient visits (99202–99215). History and exam requirements are eliminated for code selection. MDM complexity and total time become the sole determinants. Code 99201 is deleted.
2023: CMS extends the 2021 framework principles to hospital inpatient and observation codes, effective January 1, 2024.
2024–2026: AI-powered coding tools emerge, analyzing clinical notes to extract MDM elements and recommend codes in seconds rather than minutes.

Who Uses E/M Codes?

E/M codes are used across the entire healthcare delivery and billing chain:

Physicians (MDs and DOs): Select E/M codes for every patient encounter based on MDM or time. Code selection directly determines reimbursement.
Nurse Practitioners (NPs) and Physician Assistants (PAs): Bill E/M codes independently under their own NPI (at 85% of Medicare rates) or under “incident-to” billing at 100%.
Medical Coders and Billing Staff: Review physician documentation, verify E/M code accuracy, submit claims to payers, and handle denials and appeals.
Practice Managers: Monitor E/M code distribution patterns to identify undercoding, optimize revenue, and prepare for audits.
Compliance Officers and Auditors: Review E/M coding accuracy, ensure documentation supports the billed code, and flag overcoding or undercoding patterns.
Payers (Medicare, Medicaid, Commercial Insurers): Use E/M codes to process claims, determine reimbursement, and conduct post-payment audits.

Common E/M Coding Mistakes and Undercoding Statistics

E/M coding errors cost the U.S. healthcare system billions annually — both in overpayments (fraud risk) and underpayments (lost physician revenue). The most common errors are systematic undercoding patterns:

Defaulting to 99213 without scoring MDM. Many physicians habitually bill 99213 (“the safe code”) for routine visits. National Medicare data shows the average internist bills 99214 for 45–52% of established visits. If your 99213 rate exceeds 50%, you are almost certainly undercoding.
Not documenting total encounter time. Physicians who spend 35+ minutes on an encounter often qualify for 99214 or 99215 on time alone, but never capture it because they don’t record the total time in the note.
Missing data element credits. Independently interpreting a test (Category 2) or discussing management with an external physician (Category 3) upgrades the data element but is frequently undocumented. See the MDM scoring guide for details.
Undercounting chronic conditions. Two or more stable chronic conditions qualify for Low complexity — not Minimal. One chronic condition with exacerbation qualifies for Moderate. Physicians routinely undercount active problem complexity.
Ignoring prescription drug management as risk. Any encounter involving prescribing, continuing, or adjusting a prescription medication qualifies as at least Low risk. This is the single most under-scored MDM element.
Downcoding by payers without appeal. Insurance companies reduce billed codes on 5–10% of claims. Many practices accept the reduction without reviewing the documentation, which may support the original code. Learn more in our Downcoding Guide.

Studies from the AMA, MGMA, and CMS Office of Inspector General consistently report that 23–31% of E/M encounters are undercoded, representing an estimated $36 billion in annual lost revenue for U.S. physician practices.

How AI Is Transforming E/M Coding

Traditional E/M coding is a manual, time-intensive process: the physician (or coder) reads the clinical note, mentally maps documentation to MDM elements, scores each element, applies the 2-of-3 rule, checks time thresholds, and selects a code. This takes 8–12 minutes per note and is error-prone even for experienced coders.

AI-powered E/M coding tools are changing this workflow by:

Extracting MDM elements automatically. AI reads the clinical note and identifies problems addressed, data reviewed/ordered, and risk-relevant management decisions — work that previously required human interpretation of unstructured text.
Dual-code comparison. AI simultaneously calculates both MDM-based and time-based codes and recommends whichever yields higher reimbursement.
Gap analysis. AI identifies documentation gaps where adding a single sentence (e.g., “I independently interpreted the EKG”) could support a higher code level.
Audit-ready documentation. AI generates structured coding summaries that map directly to AMA 2021 guidelines, reducing audit risk.
Real-time voice coding. Ambient AI scribes transcribe the physician-patient conversation in real time and generate E/M codes before the encounter ends.

Studies show AI-assisted E/M coding recovers 12–18% more revenue than manual coding alone, primarily by catching undercoding patterns that human reviewers miss. Tools like CodeItRight.ai combine a deterministic AMA 2021 rule engine with AI extraction to ensure every recommendation is both clinically accurate and compliantly justified. Learn more about this emerging field in our guide to AI Medical Coding.

E/M Coding for Specific Specialties

While the E/M code framework is universal, different specialties face unique coding challenges:

Primary Care / Internal Medicine: Highest volume of 99213–99214 decisions. Chronic disease management visits frequently qualify for higher codes than billed. Multiple chronic conditions compound risk and data elements.
Emergency Medicine: Uses ED-specific codes (99281–99285) with different selection criteria. High documentation burden due to acuity and volume.
Psychiatry / Behavioral Health: Time-based coding is often more favorable than MDM because therapy and counseling encounters involve significant physician time with relatively straightforward MDM. See our 99213 vs 99214 upcoding guide for examples.
Surgery: Post-operative visits within the global surgical period are typically included in the surgical code and cannot be billed separately as E/M. Pre-operative consultations and unrelated conditions during the global period are exceptions.
Pediatrics: Well-child visits use preventive medicine codes (99381–99397), not E/M codes. Problem-oriented visits during a well-child appointment may be billed separately with modifier –25.

Frequently Asked Questions

What does E/M stand for in medical billing?

E/M stands for Evaluation and Management. E/M codes are a subset of CPT (Current Procedural Terminology) codes published by the American Medical Association (AMA) that describe physician encounters where a patient is evaluated, a clinical assessment is made, and a management plan is established or continued. E/M codes cover office visits, emergency department visits, hospital inpatient care, observation services, consultations, telehealth encounters, and nursing facility visits. They are the most frequently billed codes in medicine — over 500 million E/M claims are submitted to Medicare annually.

How are E/M codes selected?

Under the AMA 2021 guidelines, E/M codes for office and outpatient visits (99202-99215) are selected using one of two methods: Medical Decision Making (MDM) complexity or total encounter time — whichever yields the higher code. MDM evaluates three elements (problems addressed, data reviewed, and risk of management) and uses a 2-of-3 rule to determine one of four complexity levels: straightforward, low, moderate, or high. Time-based coding counts all physician time on the date of encounter, including face-to-face, record review, care coordination, and documentation. Physicians should document both MDM and time to preserve the option of billing whichever method produces the higher-reimbursing code.

What is the difference between new patient and established patient E/M codes?

A new patient is one who has not received any professional services from the physician or another physician of the same specialty in the same group within the past three years. An established patient has been seen within that three-year window. New patient office visits use codes 99202-99205, while established patient visits use 99212-99215. New patient codes reimburse 30-50% higher than established patient codes at the same MDM level because new encounters typically require more history gathering, examination, and documentation. Code 99211 (established patient, minimal visit) does not require physician presence and is commonly used for nurse-only visits.

What are the main E/M code families?

The major E/M code families are: Office/Outpatient visits (99202-99215) — the most commonly billed; Emergency Department visits (99281-99285) — still use the pre-2021 history/exam/MDM model; Hospital Inpatient and Observation (99221-99223 initial, 99231-99233 subsequent, 99234-99236 same-day admit/discharge); Consultations (99241-99245 outpatient, 99251-99255 inpatient); Telehealth (same 99202-99215 codes with modifier -95 or place of service 02); Critical Care (99291-99292); Nursing Facility (99304-99310); and Prolonged Services (99354-99357 for face-to-face time beyond the highest code).

How much does each E/M code reimburse?

Under 2024 Medicare national average rates, established patient office visit reimbursements are approximately: 99211 ($25), 99212 ($76), 99213 ($111), 99214 ($167), 99215 ($224). New patient visits reimburse higher: 99202 ($93), 99203 ($148), 99204 ($210), 99205 ($282). The difference between adjacent levels is significant — billing 99214 instead of 99213 adds approximately $56 per encounter. For a physician seeing 20 patients daily and correcting undercoding on just 3 visits per day, this recovers $40,000-$50,000 annually. Commercial payer rates are typically 110-150% of Medicare.

What changed with the AMA 2021 E/M guidelines?

The AMA 2021 guidelines, effective January 1, 2021, made several major changes to office and outpatient E/M coding: (1) Eliminated the requirement to document history and physical exam components for code selection — MDM complexity and time are now the only determinants. (2) Redefined time-based coding to count total physician time on the date of encounter, not just face-to-face counseling time. (3) Eliminated code 99201 (new patient, straightforward). (4) Made all levels of history and exam clinically relevant rather than code-driven. (5) Simplified data element scoring with the Category 1/2/3 framework. These changes were designed to reduce documentation burden and let physicians focus on clinical care rather than checkbox documentation.

What is E/M undercoding and how common is it?

E/M undercoding occurs when a physician bills a lower-level code than the clinical documentation supports. Studies consistently show that 23-31% of outpatient E/M encounters are undercoded, costing U.S. practices an estimated $36 billion annually in lost revenue. The most common undercoding pattern is defaulting to 99213 when documentation supports 99214 — national data shows the average internist bills 99214 for 45-52% of established visits, so practices with 99213 rates above 50% are likely leaving money on the table. Undercoding is often caused by fear of audits, failure to score MDM properly, not documenting time, and not capturing data element credits for independent test interpretation or external physician discussions.

Can telehealth visits use the same E/M codes as in-person visits?

Yes. Synchronous telehealth visits (real-time audio-video) use the same E/M codes as in-person office visits (99202-99215) with either modifier -95 (synchronous telemedicine) or place of service code 02 (telehealth). The same MDM and time-based selection rules apply. CMS made these telehealth E/M billing flexibilities permanent after initially expanding them during the COVID-19 public health emergency. Audio-only visits (telephone) use separate codes (99441-99443). Asynchronous (store-and-forward) telehealth uses code 0126T in certain states. Document the technology used and confirm patient consent for telehealth billing compliance.

How is AI changing E/M coding?

AI-powered E/M coding tools analyze clinical notes in seconds, extracting MDM elements (problems, data, risk), comparing MDM-based and time-based codes, identifying documentation gaps that could support a higher code, and generating audit-ready reports. These tools reduce the 8-12 minutes physicians typically spend on manual coding to under 30 seconds. AI also catches undercoding patterns that human reviewers miss — studies show AI-assisted coding recovers 12-18% more revenue than manual coding alone. Tools like CodeItRight.ai combine deterministic AMA 2021 rule engines with AI extraction to ensure every code recommendation is clinically and compliantly justified.

Do NPs and PAs use E/M codes?

Yes. Nurse practitioners (NPs), physician assistants (PAs), and other qualified health professionals bill E/M codes for their services using the same code families and selection rules as physicians. When billing independently (under their own NPI), NPs and PAs are typically reimbursed at 85% of the Medicare physician fee schedule rate. Under "incident-to" billing, services may be billed under the supervising physician NPI at 100% of the fee schedule, but this requires direct supervision and other CMS requirements. Certified nurse midwives, clinical psychologists, clinical social workers, and certain other non-physician providers also use E/M codes for qualifying encounters.

Start Coding Smarter Today

E/M coding determines how physicians get paid for the clinical work they do every day. Understanding the code families, selection methods, and reimbursement differences is essential for every healthcare provider and billing professional. With the AMA 2021 guidelines simplifying code selection to MDM and time, there has never been a better time to optimize your E/M coding workflow.

Explore our free resources: the E/M Cheat Sheet for quick reference, the 2026 Code Levels Chart for detailed reimbursement data, and the MDM Levels Explained deep dive on our blog. Or skip the manual work entirely — paste a note into CodeItRight.ai and get your E/M code in 30 seconds.