Emergency Medicine Billing Guide 2026
E/M Levels, Critical Care, Observation, and ED Coding
Emergency medicine billing operates in a uniquely high-volume, high-stakes environment: a busy ED sees hundreds of patients a day, each requiring a distinct E/M level assignment with documentation that must be completed in real time under clinical pressure. Emergency medicine denials are driven by E/M level downcoding (insurers bundling 99285 to 99284), critical care documentation failures, and the chronic confusion around observation status, inpatient admission, and split/shared billing with hospitalists.
This guide covers the five pillars of emergency medicine revenue: ED E/M level coding, critical care billing, observation vs. admission decision-making, procedure coding (laceration repair, fracture management, airway), and split/shared visit rules when mid-level providers are involved.
1. Emergency Department E/M Codes (99281–99285) and the ED MDM Table 2026
Since 2023, emergency department E/M levels 99281 through 99285 are chosen by medical decision making alone. History and exam only need to be medically appropriate, and time can't set the level. Two of the three MDM elements (problems, data, risk) must meet the level you bill.
ED E/M codes are unique in two ways. They're the only E/M family without a new vs. established patient distinction (every ED patient uses the same five codes), and they can't be billed by time. Since 2023 the AMA has based ED level selection on medical decision making alone, so the old three-component history, exam and MDM scoring no longer applies.
ED MDM Table 2026: 99281–99285 at a Glance
| CPT Code | MDM level | Problems addressed | Data reviewed and analyzed | Risk of management |
|---|---|---|---|---|
| 99281 | May not require a clinician | Minimal | None | Minimal |
| 99282 | Straightforward | One self-limited or minor problem | Minimal or none | Minimal |
| 99283 | Low | Two or more minor problems, or one stable chronic illness, or one acute uncomplicated illness or injury | Limited | Low |
| 99284 | Moderate | A chronic illness that's worsening, two or more stable chronic illnesses, an undiagnosed new problem with an uncertain outcome, or an acute illness with systemic symptoms | Moderate | Moderate (prescription drug management, for example) |
| 99285 | High | A chronic illness with a severe flare, or any acute or chronic illness or injury that threatens life or a body function | Extensive | High |
Typical presentations: a medication refill or minor paperwork at 99281; a simple URI or minor laceration check at 99282; a UTI with a urinalysis or mild asthma at 99283; abdominal pain or low-risk chest pain with labs and imaging at 99284; STEMI, sepsis, stroke or complex trauma at 99285.
Documenting for Level 5 (99285)
99285 is the highest-paying, most-audited ED code. To support it, two of the three MDM columns must reach the high level, and the note has to show why:
- Problems: an acute or chronic illness or injury that poses a threat to life or bodily function (sepsis, STEMI, active stroke), or a chronic illness with a severe exacerbation
- Data: extensive, meaning two of three categories: three or more items from the tests, records and independent historian group; an independent interpretation of a test someone else performed; or a documented discussion of management with an outside clinician
- Risk: high, such as drug therapy that needs intensive toxicity monitoring, a decision for emergency major surgery, a decision about hospitalization or escalation of care, or a decision to de-escalate care because of a poor prognosis
- If only one column reaches high, the visit lands on 99284. Review your templates so the highest-acuity charts capture the problem, the data and the decision, not just the diagnosis.
2. Critical Care Billing (99291–99292)
Critical care is the highest-reimbursed time-based service in emergency medicine. When documentation supports it, critical care coding generally replaces the ED E/M code for that period of care rather than adding to it. Both can be reported on the same date only when the ED visit happened first, the patient became critically ill later, and the two services are separate and documented that way. ED visit time never counts toward critical care time, and many payers expect a modifier on one of the lines, so confirm the rule your payer follows.
| CPT Code | Description | Time Requirement |
|---|---|---|
| 99291 | Critical care evaluation and management, first 30–74 minutes | Minimum 30 minutes of critical care time required; document start and end time or total time |
| 99292 | Critical care: each additional 30 minutes (add-on) | CPT: each full 30 minutes beyond 74, so the first unit starts at 75 minutes. Medicare starts the first unit at 104 minutes (see the chart below) |
Critical Care Time Chart 2026: CPT vs Medicare
CPT counts 99291 for the first 30 to 74 minutes, then 99292 for each further full 30 minutes (first unit at 75 minutes). Medicare waits until 104 minutes for the first 99292. Subtract time spent on separately billed procedures before you count anything.
| 99292 units | CPT total minutes | Medicare total minutes |
|---|---|---|
| None (99291 only) | 30–74 | 30–103 |
| 1 unit | 75–104 | 104–133 |
| 2 units | 105–134 | 134–163 |
| 3 units | 135–164 | 164–193 |
Medicare's 104-minute rule came from a CMS technical correction in the 2023 fee schedule final rule. Many commercial payers still follow the CPT timing, so check each contract before you decide how to count.
What Qualifies as Critical Care
Critical care requires two elements: (1) a critical illness or injury that acutely impairs one or more vital organ systems AND (2) physician decision-making of high complexity to prevent further deterioration or death:
- Qualifying conditions: septic shock, respiratory failure, acute MI, acute stroke, major trauma, severe metabolic derangements (DKA, severe hyperkalemia), status epilepticus, overdose with altered mental status
- Critical care time includes: time at bedside, time on unit/floor reviewing records, ordering medications, discussing with consultants, document total time and what was done during that time
- Critical care time does not include: time performing procedures that are separately billed (intubation, central line, chest tube), subtract procedure time from total critical care time
- Common documentation failure: noting "patient critically ill" without specifying which vital organ system is impaired and what clinical decisions were made, this is insufficient for 99291
3. Observation Billing: The Inpatient vs. Outpatient Decision
Observation status is one of the most misunderstood and financially consequential decisions in hospital billing. A patient in observation is an outpatient, their care is billed under outpatient rules, even if they sleep overnight in a hospital bed. This has major financial implications for both the patient (Medicare cost-sharing differences) and the provider (different billing rules).
When Observation is Appropriate
- Patient needs more than 8–10 hours of monitoring but doesn't meet inpatient admission criteria (Two-Midnight Rule for Medicare)
- Typical observation situations: chest pain rule-out, syncope workup, mild CHF exacerbation, controlled alcohol intoxication, minor head injury, post-procedural monitoring
- CMS Two-Midnight Rule: a Medicare patient is appropriate for inpatient admission if the physician expects the patient to require hospital care spanning at least two midnights; one-midnight stays are presumed appropriate for outpatient/observation
Observation E/M Billing Codes
| CPT Code | Description | Notes |
|---|---|---|
| 99234 | Observation or inpatient hospital care, low MDM, same date admit and discharge | Patient admitted and discharged same calendar date; low complexity |
| 99235 | Same date observation admit/discharge: moderate MDM | Most common same-day observation code |
| 99236 | Same date observation admit/discharge: high MDM | High complexity; requires full documentation support |
| 99218 | Observation care: initial, low MDM (admit on day 1) | Use when patient remains in observation overnight; bill admit + discharge on separate dates |
| 99220 | Observation care: initial, high MDM | High complexity initial observation |
| 99217 | Observation care: discharge | Bill on the discharge date when observation spans multiple calendar dates |
4. Procedure Billing in the ED
ED procedures are separately billable from the E/M visit and represent significant revenue that's frequently undercaptured when nursing-performed procedures are not linked to a physician order and chart note.
Laceration Repair
- Code selection depends on: anatomic location, repair type (simple/intermediate/complex), and total length of repair (sum all wounds in same layer category at same anatomic site)
- 12001–12007: Simple repair, superficial, dermis/epidermis only; wound length determines specific code (12001: ≤2.5 cm, 12002: 2.6–7.5 cm, etc.)
- 12031–12037: Intermediate repair, requires layer closure or contaminated/infected wound
- 13100–13160: Complex repair, extensive undermining, stents, retention sutures
- Add-on code 12020: treatment of wound dehiscence; 12021: with packing, both separately billable
- Modifier 59 required when billing laceration repair on same date as E/M for same wound; confirms it is a distinct procedural service
Fracture Management
- Closed treatment without manipulation: splinting only, bill application of the splint (29125–29126) separately from the E/M; the fracture management code (e.g., 25600 for distal radius) is NOT separately billable if no manipulation is performed and treatment is splinting only
- Closed treatment with manipulation: fracture management code includes splinting/casting application, don't double-bill the cast application code
- Follow-up visits within the fracture management global period are included; don't bill routine fracture checks separately
Airway and Resuscitation Procedures
| CPT Code | Description | Notes |
|---|---|---|
| 31500 | Endotracheal intubation, emergency procedure | Separately billable from critical care; subtract intubation time from critical care time |
| 92950 | Cardiopulmonary resuscitation (CPR) | Separately billable; document duration and clinical response |
| 36556 | Central venous catheter insertion: age 5+, non-tunneled | Separately billable; requires documented indication and note of insertion site/technique |
| 32551 | Tube thoracostomy: chest tube insertion | Separately billable; document laterality, size, indication |
| 99152 | Moderate sedation: first 15 minutes | Separately billable when physician performs sedation for ED procedures; document monitoring and medication doses |
5. Split/Shared Visits: PA/NP and Physician Co-Management
Split/shared visit rules underwent significant revision in 2022 and directly affect ED groups using advanced practice providers (APPs) alongside physicians. Getting this wrong creates both revenue loss and compliance exposure.
2022+ Split/Shared Rules for ED
- Effective January 2023 (fully implemented): a split/shared visit is billable under the physician's NPI only when the physician personally performs the substantive portion of the visit
- Substantive portion = more than half of the total time OR a substantive part of the medical decision making (history and exam no longer count toward it since 2024); the physician must personally perform and document one of these to bill under their NPI
- If the APP performs the majority of the visit and the physician only co-signs or does a brief review, the visit must be billed under the APP's NPI at 85% of the physician rate
- Common non-compliant practice: physician supervises but doesn't personally document their participation, the APP performs and documents, physician co-signs. This doesn't qualify for physician billing.
- Document clearly: "I personally evaluated the patient, reviewed the PA's work-up, and made the diagnosis and treatment decisions. Total time I spent on this visit: 25 minutes", this establishes the physician's substantive portion through MDM or time
RCMAXIS emergency medicine billing specialists understand the high-volume, time-sensitive nature of ED coding. Our team manages level assignment consistency, critical care documentation review, and APP billing compliance. Start with a free revenue assessment to identify your ED group's revenue improvement opportunities.
Emergency Medicine Audit Exposure: Level Selection and Critical Care
Emergency departments are reviewed at the high end. A group whose visits cluster at level 5, or one that bills critical care often, gets compared to its peers, and a mismatch between the documented medical decision making and the level billed is the usual finding. Reviewers want to see why the patient's presentation supported the level, not just that it was billed.
Critical care draws the closest look. To support 99291 the record has to show that the patient was critically ill, what the physician did, and the time spent. Time on separately billable procedures doesn't count toward critical care time. Contractors can look back three years, and because ED claims are high volume, a small documentation gap gets multiplied fast.
What an ED Level Mismatch Costs Per Shift
At the 2026 national rate, an ED visit at the highest level (99285) pays $171.35, a moderate-level visit (99284) pays $118.24, and a low-level visit (99283) pays $69.47. Critical care under 99291 pays $308.96 for the first hour when the time and criteria are documented.
If one physician sees 20 patients a shift and 3 of them are billed at 99284 when the note supports 99285, that's $159.33 a shift. Over 15 shifts a month, it comes to $2,390 a month for one provider. Critical care is where the larger misses hide, because a missed first-hour code is worth $137.61 more than the high-level visit it replaces.
Frequently Asked Questions About Emergency Medicine
What decides the ED E/M level (99281-99285)?
Since 2023, emergency department E/M levels 99281 through 99285 are chosen by medical decision making alone. History and exam only need to be medically appropriate, and time can't set the level. Two of the three MDM elements (problems, data, risk) must meet the level you bill.
How do you bill critical care time in the ED?
CPT counts 99291 for the first 30 to 74 minutes, then 99292 for each further full 30 minutes (first unit at 75 minutes). Medicare waits until 104 minutes for the first 99292. Subtract time spent on separately billed procedures before you count anything.
Do ED E/M codes distinguish new and established patients?
No. The article notes that 99281 through 99285 are the only E/M family without a new versus established distinction, so every ED patient uses the same five codes.
Can you bill an ED visit and critical care on the same day?
Sometimes. CPT allows both when the ED visit happened first, the patient later became critically ill, and the two services are separate and documented that way. Time spent on the ED visit can't count toward critical care time. Check your payer's policy on which line needs a modifier.
How does observation status affect billing?
A patient in observation is an outpatient and is billed under outpatient rules, even if they stay overnight. The article calls this one of the most consequential status decisions in hospital billing, so document the order and the reason.