CPT code 99284 is the Level 4 emergency department visit, reported when a patient has a problem of moderate to high severity and the encounter involves moderate complexity medical decision making. It sits one step below the top level 99285 and one step above 99283. Because it lands in the middle of the ED ladder, coders miss the level in both directions, and audits catch it often. So getting the moderate MDM criteria right protects real revenue.
Here is what CPT code 99284 covers, how the moderate MDM test works, why time never sets the level, and what Medicare pays in 2026.
What is CPT code 99284 used for?
You report CPT code 99284 for an emergency department visit that needs moderate complexity medical decision making. The presenting problem is serious but usually not an immediate threat to life. Think of an acute illness with systemic symptoms, a new problem with an uncertain outcome, or an injury that needs a careful workup. Any qualified provider can bill it, and the ED codes do not split into new versus established patient.
For the top of the ladder, where the problem does threaten life or function, our guide to CPT code 99285 shows how the high complexity level differs.
Moderate MDM: the two of three test for 99284
Since the 2023 E/M revisions, you select the ED level using medical decision making alone. To reach the moderate level that 99284 requires, the visit must meet or exceed two of these three elements at the moderate level:
- Problems: for example one or more chronic illnesses with exacerbation, an acute illness with systemic symptoms, or an undiagnosed new problem with an uncertain prognosis.
- Data: a moderate amount to review, such as ordering or reviewing tests, using an independent historian, or interpreting outside records.
- Risk: moderate risk, such as prescription drug management or a decision about minor surgery with patient risk factors.
Because you only need two of the three, a common 99284 pairs a moderate problem with prescription drug management, even if the data stays light. For the official element definitions, the AAPC code reference is a reliable check.
Where 99284 sits among the ED codes
Each ED code steps up by decision making complexity. Here is the moderate band in context.
| Code | ED visit level | Medical decision making |
|---|---|---|
| 99283 | Level 3 | Low |
| 99284 | Level 4 | Moderate |
| 99285 | Level 5 | High |
Why time does not apply to CPT code 99284
This point catches coders who move from clinic to emergency work: time is not a factor for ED codes. The AMA E/M guidelines and major payers agree that ED E/M levels rest solely on documented MDM. So a fast visit and a long one can both be 99284 if the decision making is moderate. That differs from office visits, where total time can drive the level, as our guide to CPT code 99214 explains.
Documentation requirements that support 99284
Since MDM carries the whole level, your note must make the moderate complexity clear. Strong 99284 documentation captures:
- The presenting problem and its severity, showing why it is more than a minor complaint.
- The data you reviewed or ordered, including any independent historian or outside records.
- The risk driving your plan, such as a prescription started or a procedure considered.
- A clear assessment and plan that ties the reasoning together.
Thin notes are costly here. In 2026, roughly one in five 99284 claims flagged in audits lacked enough MDM support, so specifics keep your level.
99284 vs 99285: where is the line?
The split between these two codes moves a meaningful amount of ED revenue. In short, 99284 needs moderate MDM, while 99285 needs the full high level on two of three elements. If the problem is serious but not life or function threatening, and the data and risk stay moderate, the visit is 99284. When a genuine threat to life pairs with high risk decisions like admission or emergency surgery, it climbs to 99285. For the analogous jump in office coding, our guide to CPT code 99215 shows how high complexity looks in a clinic.
How much does CPT code 99284 pay in 2026?
Reimbursement splits into the physician (professional) fee and the hospital (facility) payment. Under the 2026 Physician Fee Schedule, the Medicare national average for the professional component of 99284 is about $166. The facility side pays separately through the hospital outpatient system, and commercial payers often reimburse at 110% to 150% of the Medicare rate depending on the contract. So always confirm the payer and setting before you bill.
Common 99284 billing mistakes to avoid
- Weak MDM documentation. This is the top reason 99284 claims fail on audit.
- Trying to bill by time. A long ED visit alone does not support 99284, because only MDM sets the level.
- Upcoding to 99285. Reaching for the level 5 without a life threatening problem and high risk invites denials.
- Downcoding to 99283. Dropping to low MDM out of caution costs earned revenue on moderate visits.
Key takeaways
- CPT code 99284 is the Level 4 emergency department visit for a moderate to high severity problem with moderate complexity MDM.
- You select it by medical decision making alone, because time is not a factor for ED codes.
- Moderate MDM needs two of three at the moderate level: moderate problems, moderate data, or moderate risk.
- The 2026 Medicare professional average is about $166, with commercial payers often paying more.
Frequently asked questions
What is CPT code 99284 used for?
It reports a Level 4 emergency department E/M visit for a problem of moderate to high severity that requires moderate complexity medical decision making. Any qualified provider can bill it in the emergency department setting.
Does time determine the 99284 level?
No. Emergency department E/M codes are selected by medical decision making only. Time is not a descriptive component for ED codes, so documented MDM complexity sets the level.
What is the difference between 99284 and 99285?
99284 requires moderate complexity MDM, while 99285 requires high complexity MDM on two of three elements. A genuine threat to life or function paired with high risk decisions pushes a visit from 99284 to 99285.
What MDM is required for 99284?
Moderate complexity. The visit must meet two of three at the moderate level: moderate problems such as an acute illness with systemic symptoms, moderate data, or moderate risk such as prescription drug management.
How much does Medicare pay for 99284 in 2026?
The professional component averages about $166 nationally under the 2026 Physician Fee Schedule, with the hospital facility payment billed separately. Commercial payers often reimburse at 110% to 150% of the Medicare rate.
CPT code 99284 sits at the busy center of emergency coding, which is exactly why it costs practices money when the note falls short. Document the problem’s severity, the data you weighed, and the risk behind your plan, and the moderate level holds up on review. Code it honestly against 99283 below and 99285 above, and 99284 becomes a reliable, defensible claim. For the full picture, keep our complete guide to CPT codes close by.
