CPT 99233 reports a subsequent hospital inpatient or observation care visit, per day, that requires a high level of medical decision making (MDM) or at least 50 minutes of total practitioner time on the date of the encounter.
99233 is the top level of the three subsequent-day hospital codes, and it is where hospitalists, intensivists, infectious disease physicians and other inpatient consultants carry the most audit exposure. Payers and auditors compare the level billed with what the note proves: a high-risk problem, the data the practitioner actually reviewed, and a management decision with real risk, or a credible total-time statement.
The rules changed significantly on 1 January 2023. Observation and inpatient visits now share the same codes, history and exam no longer drive the level, and time means all of the practitioner’s work on that date, not just time on the unit or floor. Many templates and older guides still reflect the pre-2023 rules.
This guide covers how to qualify 99233 by MDM or time, how to report prolonged time for Medicare (G0316) and other payers (99418), split/shared billing, 2026 Medicare payment, and a worked example.
Key Takeaways
- 99233 requires a medically appropriate history and/or examination plus high MDM, or 50 minutes of total time on the date of the encounter that must be met or exceeded.
- Since 2023, 99231 to 99233 cover both inpatient and observation stays. The old observation codes 99217 to 99220 and 99224 to 99226 were deleted.
- Under the 2026 Medicare Physician Fee Schedule, 99233 carries 3.20 total RVUs, about $106.88 nationally before geographic adjustment at the $33.4009 conversion factor.
- For Medicare, report extra time with G0316 once total time reaches 65 minutes. CPT code 99418 is for payers that follow CPT rules.
- A split/shared 99233 is billed by the practitioner who performed the substantive portion (more than half of the total time, or a substantive part of the MDM), with modifier FS.
What CPT 99233 Means
The AMA describes 99233 as subsequent hospital inpatient or observation care, per day, for the evaluation and management of a patient, which requires a medically appropriate history and/or examination and a high level of medical decision making. When total time on the date of the encounter is used for code selection, 50 minutes must be met or exceeded.
Subsequent means the patient has already received an initial hospital inpatient or observation service from the same practitioner, or from another practitioner of the same specialty in the same group, during the stay. Most stays use one initial code (99221 to 99223), a series of subsequent codes, and a discharge code.
| Code | Medical decision making | Total time on the date |
|---|---|---|
| 99231 | Straightforward or low | 25 minutes |
| 99232 | Moderate | 35 minutes |
| 99233 | High | 50 minutes |
You choose the level by MDM or by time, whichever better supports the visit. You do not need both. The history and exam must be medically appropriate, but they no longer count toward the level.
How to Qualify 99233 by Medical Decision Making
High MDM requires two of the three MDM elements to reach the high level. Use the AMA MDM table, which applies to all E/M families, including the office codes covered in our 99214 CPT code guide.
| MDM element | What high looks like | Inpatient examples |
|---|---|---|
| Problems | One or more chronic illnesses with severe exacerbation, progression or side effects of treatment, or an acute or chronic illness or injury that poses a threat to life or bodily function | Septic shock, worsening respiratory failure, acute kidney injury on chronic kidney disease |
| Data | Extensive: at least two of three categories (see below) | Reviewing new labs and cultures, independently reading a chest image, discussing management with another specialist |
| Risk | High risk of morbidity from additional diagnostic testing or treatment | Drug therapy requiring intensive monitoring for toxicity, decision regarding escalation of hospital-level care, decision about emergency major surgery, decision not to resuscitate or to de-escalate care |
Extensive data, Category 1. Any combination of three: review of prior external notes from each unique source, review of the result of each unique test, ordering of each unique test, or an assessment requiring an independent historian.
Extensive data, Category 2. Independent interpretation of a test performed by another physician or qualified health care professional, when not separately reported.
Extensive data, Category 3. Discussion of management or test interpretation with an external physician, qualified health care professional or appropriate source, when not separately reported.
Under AMA rules, ordering a test includes reviewing its result, so a test ordered yesterday and reviewed today should not be counted twice. On subsequent days, the strongest 99233 notes show something new: a change in status, a new decision, or a reassessment of a high-risk treatment.
Do not choose 99233 because the diagnosis sounds serious. A patient with sepsis who is improving on oral antibiotics and awaiting discharge planning often supports 99232. The note must show high-level problems and risk on that date, not on the date of admission.
How to Qualify 99233 by Time
Time is the total time the physician or other qualified health care professional personally spends on the patient on the date of the encounter, face-to-face and non-face-to-face. For 99233, the total must be at least 50 minutes.
- Counts: preparing to see the patient, such as reviewing tests and records.
- Counts: obtaining or reviewing separately obtained history, examining the patient, and counseling the patient, family or caregiver.
- Counts: ordering medications, tests or procedures, and communicating with other health care professionals when not separately reported.
- Counts: documenting in the medical record, and independently interpreting and communicating results when not separately reported.
- Does not count: clinical staff time, time spent on separately reported services, or general teaching not related to the patient.
A start and stop time is not required. A clear statement of total time on that date, plus the activities, is what reviewers expect. For example: “I spent 55 minutes on this patient’s care today, including reviewing overnight labs and imaging, examining the patient, discussing the plan with nephrology, and documenting.”
Prolonged Services: G0316 vs 99418
When 99233 is selected by time and the practitioner spends at least 15 minutes beyond the threshold, a prolonged service code may apply. Medicare and CPT use different codes but, since a CMS correction in 2023, the same starting point for 99233.
| Total time on the date | Medicare | Payers that follow CPT |
|---|---|---|
| 50 to 64 minutes | 99233 | 99233 |
| 65 to 79 minutes | 99233 + G0316 x 1 | 99233 + 99418 x 1 |
| 80 to 94 minutes | 99233 + G0316 x 2 | 99233 + 99418 x 2 |
| 95 minutes or more | 99233 + G0316 x 3 or more | 99233 + 99418 x 3 or more |
Medicare does not accept 99418 for inpatient and observation visits; G0316 is its equivalent. Medicare contractors also state that G0316 should not be reported for any unit of less than 15 minutes, should not be billed on the same date as 99358, 99359, 99415, 99416 or 99418, and is not reportable with discharge day management codes. Check commercial and Medicaid policies, because some plans do not pay prolonged services at all.
99233 vs Similar or Confused Codes
| Code | What it reports | When to use it instead of 99233 |
|---|---|---|
| 99232 | Subsequent visit, moderate MDM or 35 minutes | The patient is stable or improving and the decisions are moderate risk |
| 99223 | Initial visit, high MDM or 75 minutes | This is the practitioner’s first inpatient or observation service of the stay |
| 99236 | Same-day admission and discharge, high MDM or 85 minutes | The same practitioner admits and discharges on the same date |
| 99238 / 99239 | Discharge day management, 30 minutes or less / more than 30 minutes | The visit is the discharge day; do not bill 99233 for it |
| 99291 | Critical care, first 30 to 74 minutes | The patient is critically ill and the practitioner provides critical care |
| 99252 to 99255 | Inpatient or observation consultation | Non-Medicare payers that still pay consults; Medicare does not pay consultation codes |
Medicare allows a hospital visit and critical care by the same practitioner on the same date only when the visit took place before the patient needed critical care, with modifier 25 and documentation that supports both. Our critical care billing team reviews these combinations before submission.
2026 Medicare Payment for 99233
The figures below are national, non-qualifying APM participant amounts from the 2026 CMS relative value file, calculated as total RVUs times the $33.4009 conversion factor. Actual payment varies by locality (GPCI), and Medicare pays 80% after the Part B deductible, with the patient owing the coinsurance.
| Code | Work RVU | Total RVU (facility) | National amount |
|---|---|---|---|
| 99231 | 1.00 | 1.32 | $44.09 |
| 99232 | 1.59 | 2.11 | $70.48 |
| 99233 | 2.40 | 3.20 | $106.88 |
| 99223 | 3.50 | 4.68 | $156.32 |
The gap between 99232 and 99233 is about $36 per visit at the national rate. That makes 99233 valuable on a long stay, and it is also why auditors sample it.
Split/Shared 99233 Visits
In hospital settings, a physician and a nonphysician practitioner (NP or PA) in the same group can share a visit. Since 1 January 2024, CMS defines the substantive portion as more than half of the total time spent by the physician and NPP, or a substantive part of the MDM as defined by the CPT E/M guidelines. The practitioner who performed the substantive portion bills the visit.
- Add modifier FS to every split/shared claim line.
- When billing by time, add both practitioners’ time, but count overlapping time once.
- Document who performed which part, and have the billing practitioner sign the note.
- Split/shared rules do not apply in the office or in nursing facilities.
If billed under the NPP, Medicare pays 85% of the physician fee schedule amount.
Billing Rules That Trigger 99233 Denials
One visit per day. Medicare pays one subsequent visit per calendar date for practitioners of the same specialty in the same group. Two notes on the same day must be combined into one level, or the second line may deny as a duplicate, often with CO-18.
Global surgery. A surgeon’s routine post-operative hospital visits are included in the global payment and are not separately billable. Unrelated visits need the right modifier, or they deny as bundled, often with CO-97.
Place of service. Use the POS that matches the patient’s status on that date: 21 for inpatient, and an outpatient hospital code such as 22 or 19 for observation. See how POS 21 affects billing.
Initial vs subsequent. Under Medicare, a practitioner of a different specialty may bill an initial code for their first visit of the stay; the admitting practitioner adds modifier AI. A second practitioner of the same specialty and group must bill subsequent codes.
Worked Example: Day 3 of a Hospital Stay
A Medicare patient admitted for pneumonia develops worsening acute kidney injury and falling blood pressure on day 3. An infectious disease physician reviews new cultures and the basic metabolic panel, independently reviews the chest imaging, changes vancomycin to an alternative because of toxicity risk, discusses the case with nephrology, and talks with the hospitalist about transfer to the ICU. The note records 72 minutes of total time on that date.
| Element | Finding | Level |
|---|---|---|
| Problems | Acute illness posing a threat to bodily function | High |
| Data | Category 1 (tests reviewed), Category 2 (independent imaging review) and Category 3 (discussion with nephrology) | Extensive |
| Risk | Decision regarding escalation of hospital-level care | High |
| Time | 72 minutes | Over 65 minutes |
Result. MDM supports 99233. Because time also reached the 65 to 79 minute band, Medicare can be billed 99233 + G0316 x 1. A commercial payer that follows CPT would receive 99233 + 99418 x 1, if its policy pays prolonged services.
If the physician had not recorded total time, the claim would still support 99233 on MDM alone, but there would be no basis for the prolonged service code. Infectious disease groups see this often, which is why our infectious disease billing reviews check time statements as well as MDM.
Before You Bill 99233: A 5-Step Check
- Confirm the code family. The patient is inpatient or observation, and this is not the practitioner’s first visit or the discharge day.
- Score MDM for this date. Two of three elements must reach high, based on what happened today.
- Check time. If time is the better path, confirm a total-time statement of 50 minutes or more with activities listed.
- Check same-day services. Combine same-specialty notes, check global periods and critical care, and add FS for split/shared visits.
- Add prolonged time correctly. Use G0316 for Medicare and 99418 for CPT payers, only in full 15-minute units.
If a payer downcodes a well-documented 99233, request a review with the note and an MDM summary. Our guide to the medical claim appeal process explains the levels and deadlines. Practices that bill mostly inpatient E/M can also see how our internal medicine billing services support hospitalist groups.
Want an expert second look at your 99232 and 99233 mix before an auditor does? Steady Medical Billing’s medical coding services review inpatient E/M notes against current AMA and CMS rules.
Frequently Asked Questions
What is CPT code 99233?
CPT 99233 is subsequent hospital inpatient or observation care, per day, that requires a medically appropriate history and/or examination and high medical decision making, or at least 50 minutes of total practitioner time on the date of the encounter.
How many minutes are required for 99233?
At least 50 minutes of total time by the physician or qualified health care professional on the date of the encounter, counting face-to-face and non-face-to-face work. At 65 minutes, add G0316 for Medicare or 99418 for payers that follow CPT.
How much does Medicare pay for 99233 in 2026?
99233 has 3.20 total RVUs in 2026. At the $33.4009 conversion factor, the national amount is about $106.88 before geographic adjustment, and actual payment varies by locality.
Can 99233 be billed for observation patients?
Yes. Since 1 January 2023, 99231 to 99233 report subsequent visits for both hospital inpatient and observation patients. The old observation codes were deleted.
Can a nurse practitioner or physician assistant bill 99233?
Yes, within their scope of practice. Billed under the NPP, Medicare pays 85 percent of the fee schedule amount. For a split/shared visit, the practitioner who performed the substantive portion bills it with modifier FS.
