E/M Billing Calculator
2021/2023 AMA MDM Guidelines
Neurowiki Billing
2021/2023 AMA MDM Framework
Rapid Entry
POS: 21 — Inpatient Hospital
Medical Decision Making
Level: MINMinimal Complexity
Self-limited or minor problem. No prescription drug management.
Select the complexity that best matches the problems addressed at this visit.
Data Reviewed
MINCat 1 — Tests, Documents & Historian(≥2 = Low · ≥3 = Moderate)
Cat 2 — Independent Interpretation(alone = Moderate)
Cat 3 — Provider Discussion(alone = Moderate)
Management
MINSelect the single most complex action — MDM uses the highest risk level only.
Initial Hospital Inpatient/Observation — Low Complexity MDM
This visit type has no minimal-complexity code — floor code shown per AMA guidelines.
CPT: 99221 Epic Charge: Initial Hospital Care Level 1 ICD-10: [No diagnoses entered] DOS: 06/11/2026 POS: 21 — Inpatient Hospital
No separate attestation needed — sign your progress note as usual.
MDM Justification
Live · Reference onlySelect problem complexity above
No data elements checked
No management risk selected
Problems + Data + Risk qualify at MINIMAL — 2-of-3 rule satisfied
Supported Specialties
This E/M billing calculator is designed for practicing physicians across multiple specialties: Neurology (stroke, seizure, dementia, headache — including neurohospitalist workflows), Internal Medicine and Hospitalist Medicine (initial and subsequent inpatient care, discharge planning), Emergency Medicine (MDM-only ED coding per 2023 AMA), Cardiology, Psychiatry, Family Medicine, and Surgery. Each specialty comes with pre-populated MDM examples for common diagnoses, imaging, labs, and management risk levels. Use the NPI lookup to auto-populate your specialty from the CMS NPPES registry.
CPT codes and E/M guidelines based on 2021/2023 AMA CPT revisions and CMS Medicare Claims Processing Manual. For educational and reference use only — verify with your institutional compliance team. CPT® is a registered trademark of the American Medical Association.
Frequently asked questions
How do I choose between CPT 99205 and 99215?
99205 is for new patients with high-complexity MDM or 60+ minutes of total time. 99215 is for established patients with high-complexity MDM or 54+ minutes. Both require high-complexity medical decision-making: typically a problem with threat to life or bodily function, extensive data review, and high-risk management (e.g., starting/adjusting a high-risk medication, IV drug therapy, or a major surgery decision). For established patients, 99213 (low), 99214 (moderate), and 99215 (high) map to the same MDM levels as 99203, 99204, and 99205 for new patients.
What is the 2021 AMA E/M MDM framework?
Since January 2021, outpatient E/M codes (99202–99215) are selected based on Medical Decision-Making (MDM) or total time — not documentation of history and physical exam. MDM has three elements: (1) Number and complexity of problems addressed, (2) Amount and/or complexity of data reviewed and analyzed, and (3) Risk of complications and/or morbidity or mortality of patient management. The overall MDM level is determined by meeting at least 2 of 3 elements at a given level (minimal, low, moderate, or high).
What CPT codes do hospitalists use for inpatient billing?
Hospitalists use 99221–99223 for initial hospital care (low/moderate/high MDM or 40–75+ minutes) and 99231–99233 for subsequent hospital care (low/moderate/high MDM or 25–50+ minutes). Discharge day management uses 99238 (≤30 minutes) or 99239 (>30 minutes). For critical care, 99291 covers the first 30–74 minutes and 99292 each additional 30 minutes.
Can I bill E/M codes by time in 2023?
Yes. Since 2021, total physician time on the date of service is a valid sole basis for E/M level selection for office and outpatient visits (99202–99215). For inpatient and subsequent visits (99221–99233), time-based billing is also permitted. Emergency department visits (99281–99285) are the exception — per 2023 AMA guidelines, time is not a valid basis for ED E/M code selection; MDM must be used.
What is the difference between MDM-based and time-based E/M billing?
MDM-based billing selects the CPT code based on problem complexity, data reviewed, and management risk — regardless of how long the visit takes. Time-based billing selects the CPT code based on total physician time on the date of the encounter (including pre-charting, exam, counseling, and documentation). You may choose whichever method supports the highest code for any given encounter. Neither method requires documenting that you chose it — simply meet the criteria for the level you are billing.
What is a -GC modifier and when is it used for E/M billing?
The -GC modifier (Teaching Physician performed or supervised service) is added to an E/M code when a resident is present and the attending physician personally performs the key or critical portion of the service and is present during the resident's key portions. The attestation must document the attending's personal participation and evaluation, not merely supervisory presence. In the primary care exception (PCTE), supervision rules are relaxed for certain low-complexity office visits.