CPT 99233: subsequent hospital care, high decision making
99233 reports a follow-up visit to a hospital inpatient or observation patient when the decision making is high, or when total time on the date reaches 50 minutes. It is the top subsequent hospital care level and the only subsequent level that Medicare pairs with a prolonged service code.
Written by Salman Saeed, CEO and Co-Founder · Reviewed by a Certified Medical Coder · Last reviewed October 2026In short: 99233 is selected by high MDM or by 50 minutes of total time, whichever the note supports. When time sets the level and the day runs to 65 minutes, Medicare adds G0316 for each further 15 minutes. Sicker patients also raise the question of critical care on the same date.
What does CPT 99233 report?
99233 is the highest of the follow-up hospital visit codes for inpatient and observation care. The CY 2026 fee schedule final rule prints the descriptor: a medically appropriate history or exam and high MDM, or at least 50 minutes of total time on the date of the encounter when time is used to choose the code.
| Item | Value in the file |
|---|---|
| Short label CMS uses | Sbsq hosp ip/obs high 50 |
| Payment status | A (active code) |
| Work RVU | 2.40 |
| Facility total RVU | 3.20 |
| Global period | XXX |
How do you bill 99233 by time or by MDM?
MLN006764 says that for most E/M visit families you choose the level by MDM or by the time spent. The history and exam must still meet the code descriptor, but they do not set the level.
| Basis | What the note must show | Trap |
|---|---|---|
| High MDM | The problems addressed, data reviewed or ordered and the risk of the management decisions, scored against the AMA E/M guidelines | A long note that lists findings but not the decisions |
| 50 minutes of total time | Total minutes on the date, or a start and stop time, for the practitioner's own qualifying work | 49 minutes does not count: MLN006764 says the CPT midpoint rule does not apply |
Section 30.6.9 B of Chapter 12 says a continuous service that spans two calendar dates is one service, reported on the date the encounter began, and all of its time may count toward that date.
When can you add G0316 to 99233?
CPT's own prolonged inpatient code is not what Medicare uses. In RVU26D, 99418 has status I, while G0316 has status A. The October 2026 HCPCS file describes G0316 as each additional 15 minutes beyond the total time of the primary service, listed with 99223, 99233 or 99236, when the primary service was selected by time.
Chapter 12, section 30.6.15.3, and MLN006764 Table 4 give the threshold for 99233 as 65 minutes, counted on the date of the visit. That is the 50 minute label plus 15. Section 30.6.15.3 adds that CMS assigns no frequency limit and that prolonged services are not reported with emergency department visits or critical care.
A hospitalist records 82 total minutes on one date and selects the level by time. That is 32 minutes past the 50 minute label, so two full 15-minute units. The claim carries 99233 and G0316 with 2 units.
What if the patient becomes critically ill the same day?
Chapter 12, section 30.6.9 A, says that while a practitioner is managing a critically ill patient, services that do not reach the level of critical care are reported with a subsequent hospital care code from 99231 to 99233. Hospital visits and critical care can be billed the same day in the circumstances in section 30.6.12.
Section 30.6.12.6 sets the conditions for billing both: the other E/M visit happened before the critical care, at a time the patient did not need critical care, it was medically necessary, and it was separate from the critical care work. Modifier 25 goes on the critical care code. NCCI policy bars double counting time, so minutes used for 99233 do not also count toward 99291. See critical care billing.
Can 99233 be furnished by telehealth?
In the CY 2026 final rule (90 FR 49266), CMS finalized eliminating the telehealth frequency limitations for subsequent inpatient hospital visits, and listed 99231, 99232 and 99233 among the affected codes. CMS adds that practitioners should use professional judgment on the modality for each patient.
How does 99233 appear on the claim, and what edits apply?
On the CMS-1500, Item 24D carries 99233, Item 24G carries 1 unit and Item 24B carries the place of service from Chapter 26: 21 for a registered inpatient, 22 for an on-campus outpatient, 19 for an off-campus outpatient. Do not append AI; that modifier belongs on the initial care code.
The NCCI practitioner MUE table effective October 1, 2026 lists 99233 at 1 per date, adjudication indicator 3. G0316 is a separate line with its units.
What does the 99233 line look like on the CMS-1500?
99233 goes in Item 24D with 1 unit in Item 24G and the Item 24B place of service. When G0316 follows it, the second line repeats the date and place of service and carries the added 15-minute units in Item 24G.
Why is 99233 denied or downcoded?
| Code | What X12 says | What usually causes it |
|---|---|---|
| CO-150 | The payer deems the information submitted does not support this level of service | The note has no total time and the decisions do not read as high MDM |
| CO-50 | Non-covered because the payer does not deem it medically necessary | The record does not show why a daily visit was needed |
| CO-151 | The information does not support this many or this frequency of services | Visits or G0316 units the payer says the record does not support |
| OA-18 | Exact duplicate claim or service | A covering physician in the same group billed the same date |
If these denials keep coming back, our denial management team can work them. The lower levels are 99231 and 99232.
Related codes
- Medicare Claims Processing Manual, Chapter 12: Physicians/Nonphysician Practitioners · CMS
- Medicare Claims Processing Manual, Chapter 26: Completing and Processing Form CMS-1500 Data Set · CMS
- Physician Fee Schedule relative value files, RVU26D (October 2026) · CMS
- Medicare NCCI Medically Unlikely Edits, practitioner services table, effective 10-01-2026 · CMS
- Evaluation and Management Services (MLN006764, May 2026) · CMS
- HCPCS quarterly update, October 2026 alpha-numeric file · CMS
- 2026 NCCI Medicare Policy Manual, Chapter XI: Medicine and Evaluation and Management Services · CMS
- CY 2026 Physician Fee Schedule final rule (90 FR 49266) · Federal Register
- Claim Adjustment Reason Codes · X12
- Place of service code set · CMS
We check every rule, code and deadline against the official source. See our editorial policy.
Common questions
Straight answers from the team that does the work.
Ask a billing lead directly. A 20-minute call, Monday to Friday, 9am to 5pm Eastern.
01How do I bill subsequent hospital care by time or MDM?
Choose one basis per date. For 99233, either document high medical decision making or total time of 50 minutes or more on the date. MLN006764 says history and exam must fit the descriptor but do not set the level, and that you should record total minutes or a start and stop time.
02How many minutes do I need for 99233?
Fifty minutes of total time on the date must be met or exceeded, per the CY 2026 final rule descriptor. CMS says the CPT midpoint rule does not apply, so 49 minutes supports 99232 (35 minutes), not 99233, unless the decision making is high.
03Does Medicare pay prolonged service with 99233?
Yes, as G0316 rather than CPT 99418. The threshold is 65 total minutes on the date of the visit, with the level chosen by time, and each additional 15 minutes is one unit. Chapter 12 section 30.6.15.3 says there is no frequency limit.
04Can I bill 99233 and critical care on the same day?
Sometimes. Chapter 12 section 30.6.12.6 allows both when the visit came before the critical care, when the patient did not yet need critical care, and the services were separate and medically necessary. Modifier 25 goes on the critical care code.
05What is the denial for a 99233 payer says is too high?
Usually CARC 150, which X12 defines as the payer deeming the information submitted not to support the level of service. Appeal with the total time or the high MDM elements from the note, or accept a lower level the record supports.
High-level rounding visits getting cut?
We check the time or MDM support in each note and appeal the downcodes.