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Prolonged services time thresholds are one of the few genuinely determinate things in E/M coding. There is a correct number of minutes for each base code, published by CMS in a table. And yet these get billed wrong constantly — because there are two different arithmetics in circulation, because the counting window is not always the day of the visit, and because “15 more minutes” does not mean what most people assume.
This guide sets out the Medicare numbers, where they come from, and the four rules that determine whether a given minute counts.
The two arithmetics
Before any table is useful, you have to know which rule you are applying.
The CPT rule starts prolonged time after the minimum required time of the primary service. CMS quoted the CPT 2021 descriptor for 99417 as reading “beyond the minimum required time of the primary procedure which has been selected using total time.”
The Medicare rule starts prolonged time after the maximum required time, or, for the non-office families, after the total time in the CMS time file. CMS’s stated principle in the CY 2023 final rule is that “prolonged services can be reported if the physician or NPP spends 15 or more minutes beyond the total time.”
CMS adopted the second rule to avoid double-counting. Its example: for 99215, range 40–54 minutes, “if the reporting practitioner spent 55 minutes of time, 14 of those minutes are included in the services described by CPT code 99215. Therefore, only 1 minute should be counted towards the additional 15 minutes needed.”
Everything below is the Medicare rule. For the comparison with CPT, see our guide to 99417 versus G2212.
Office and outpatient visits: G2212
CMS publishes this as Table 3 of its Evaluation and Management Services booklet (MLN006764, May 2026). Times are total reportable time on the date of service, including the prolonged time.
| Codes reported | Total time required |
|---|---|
| CPT 99205 | 60–74 minutes |
| 99205 × 1 and G2212 × 1 | 89–103 minutes |
| 99205 × 1 and G2212 × 2 | 104–118 minutes |
| CPT 99215 | 40–54 minutes |
| 99215 × 1 and G2212 × 1 | 69–83 minutes |
| 99215 × 1 and G2212 × 2 | 84–98 minutes |
| 99215 × 1 and G2212 × 3 or more, for each additional 15 minutes | 99 minutes or more |
Two observations that answer most of the questions people have about this table.
First, look at the gap between the base code and the first prolonged unit. A 99205 visit tops out at 74 minutes, but G2212 does not become reportable until 89. Minutes 75 through 88 are billable as nothing — they are already inside what 99205 pays for, plus the incomplete prolonged increment. There is a real dead zone, and it is 14 minutes wide. This is not an oversight; it is the direct consequence of CMS’s anti-double-counting position.
Second, each band is 15 minutes wide once you are in prolonged territory, because each additional unit requires a complete 15 minutes.
CMS restates the operative criteria for G2212 as: use it “for services beyond the maximum time of the primary service you select using total time on the date of the primary service”; “for each additional 15 minutes beyond the maximum time you provide, with or without direct patient contact”; list it separately in addition to CPT 99205, 99215 or 99483; do not report it on the same date of service as CPT 99358, 99359, 99415 or 99416; and “don’t report HCPCS code G2212 for less than 15 additional minutes.”
The other E/M families: G0316, G0317, G0318
CMS publishes this as Table 4 of the same booklet. This is the table worth keeping on a wall, because the thresholds are not derivable from the CPT descriptors and the counting windows differ by family.
| Primary E/M service | Prolonged code | Time threshold | Count time within |
|---|---|---|---|
| Initial inpatient or observation visit (99223) | G0316 | 90 minutes | Date of visit |
| Subsequent inpatient or observation visit (99233) | G0316 | 65 minutes | Date of visit |
| Same-day admission and discharge (99236) | G0316 | 110 minutes | Date of visit to 3 days after |
| Inpatient/observation discharge day management (99238–99239) | N/A | N/A | N/A |
| Emergency department visits | N/A | N/A | N/A |
| Initial nursing facility visit (99306) | G0317 | 95 minutes | 1 day before + date of visit + 3 days after |
| Subsequent nursing facility visit (99310) | G0317 | 85 minutes | 1 day before + date of visit + 3 days after |
| Nursing facility discharge day management | N/A | N/A | N/A |
| Home or residence visit, new patient (99345) | G0318 | 140 minutes | 3 days before + date of visit + 7 days after |
| Home or residence visit, established patient (99350) | G0318 | 110 minutes | 3 days before + date of visit + 7 days after |
| Cognitive assessment and care planning (99483) | G2212 | 100 minutes | 3 days before + date of visit + 7 days after |
| Consultations | N/A | N/A | N/A |
CMS footnotes the table: “You must use time to select your visit level.”
The counting window is the part people miss
For office and outpatient visits, prolonged time is counted on the date of service. Simple.
For the other families it is not. CMS aligned each window to the timeframe the AMA RUC actually surveyed when valuing the primary service. So:
- Inpatient and observation initial and subsequent visits: the date of the visit only.
- Same-day admission and discharge: the date of the visit through three days after.
- Nursing facility visits: one day before, the date of the visit, and three days after.
- Home or residence visits, and cognitive assessment: three days before, the date of the visit, and seven days after — an eleven-day window.
CMS confirmed the home and residence window explicitly when a commenter asked: “The prolonged time can occur on the date of the visit, or within the 3 days prior or 7 days after the visit date. These 11 days comprise the service period used by the AMA RUC to develop recommended values for home or residence visits.”
This cuts both ways. Practices lose money by counting only same-day minutes on a home visit. And practices create exposure by counting minutes from outside the window for an inpatient visit, where the window is the date of service alone.
One useful consequence CMS spelled out: where a nursing facility initial visit and an emergency department visit are furnished by the same practitioner on the same day and time is used to select the NF visit level, “the time spent by the practitioner for the ED visit can be counted toward prolonged NF services (G0317).”
Why the thresholds are round numbers
They were rounded on purpose. CMS: “Since practitioners may find it easier to follow time thresholds for reporting that are rounded, we are rounding all of the total times to the nearest 5 minutes… This results in rounding down the reporting time thresholds for prolonged Other E/M services by 1 or 2 minutes in several instances.”
The clearest illustration is 99483. Its total time is 101 minutes; CMS set the threshold at 100. As CMS put it, this “results in a prolonged services reporting threshold of 100 minutes (1 minute lower than the total time of 101 minutes).”
So the rounding is in the practitioner’s favour, slightly, and the published number is the operative one — do not recompute it from the underlying time file.
A discrepancy worth knowing about
If you read the CY 2023 PFS final rule preamble alongside the published table, you will find an apparent conflict on G0316. The preamble discussion describes the mechanism this way: for 99223, “the prolonged service period would begin at 90 minutes, 15 minutes beyond 75 minutes. A practitioner would bill HCPCS code G0316 once the 15-minute increment for G0316 is completed, at minute 105.”
CMS’s published reporting table — Table 4 of MLN006764, the current May 2026 edition — gives the threshold for 99223 as 90 minutes.
The published threshold table is the operative guidance and is what MACs administer. If a reviewer challenges a G0316 claim at 90 minutes, MLN006764 Table 4 is the citation to hold. It is worth knowing the preamble language exists so that it does not ambush you mid-appeal.
The four rules that decide whether a minute counts
- Time must have been used to select the visit level. If you selected the level on medical decision making, there is no prolonged service to report, however long the encounter ran.
- Only qualifying activities count. CMS points to the AMA E/M Services Guidelines, “Guidelines for Selecting Level of Service Based on Time,” for the list, and requires that “your services are medically reasonable and necessary.”
- The increment must be complete. “Don’t report HCPCS code G2212 for less than 15 additional minutes.” A partial unit is not billable and never rounds up.
- The minute must fall inside the counting window for that E/M family.
Split or shared visits
Where a physician and an NPP in the same group both contribute in a facility setting, CMS pays whoever performed the substantive portion. For prolonged visits specifically, CMS states: “Starting in 2024, for prolonged visits, the substantive portion is more than 50% of the practitioner’s total time.” The claim must carry the designated split or shared modifier, and the record must identify both practitioners, with the billing practitioner signing and dating. See MLN Matters MM13592.
What has no prolonged service code at all
Emergency department visits, discharge day management (inpatient, observation and nursing facility), consultations, and critical care. CMS’s reason for the ED exclusion is that “the ED visit codes are not reported based on the amount of time spent with the patient” — there is no base time for a prolonged increment to run from.
Also unavailable to Medicare: CPT 99358 and 99359, which CMS assigned status indicator “I,” meaning not valid for Medicare purposes. CPT 99354–99357 were deleted outright by the CPT Editorial Panel effective 2023.
Frequently asked questions
At how many minutes can I bill a prolonged office visit to Medicare?
89 minutes for a new patient visit built on 99205, and 69 minutes for an established patient visit built on 99215. Both figures are total time on the date of service, inclusive of the prolonged time.
Why can’t I bill a prolonged code at 75 minutes for a 99205?
Because 99205 already pays for up to 74 minutes, and a prolonged unit requires a further complete 15 minutes. 74 plus 15 is 89. Under CPT rules the answer would be different — 75 minutes — which is the source of most of the confusion.
Can prolonged time be counted on a different day than the visit?
For office and outpatient visits, no — date of service only. For nursing facility, home or residence, same-day admission and discharge, and cognitive assessment services, yes, within the specific windows in the table above.
Do I round 12 minutes up to a unit?
No. CMS is explicit that the code must not be reported “for any time unit less than 15 minutes.” There is no midpoint rule here — CMS considered and rejected that reading.
Can I bill prolonged services with a level 4 visit?
No. Prolonged codes attach to the highest level in the family — 99205, 99215, 99223, 99233, 99236, 99306, 99310, 99345, 99350, plus 99483.
Can I report both G2212 and 99415 on the same day?
No. G2212 must not be reported on the same date of service as 99358, 99359, 99415 or 99416. Codes 99415 and 99416 describe prolonged clinical staff time, which is a different resource entirely.
Does G2211 have a time threshold?
No. G2211 is a complexity add-on with no time component and no relationship to prolonged services. See our guide to the G2211 visit complexity add-on code.
Sources
- CMS MLN Booklet MLN006764, Evaluation and Management Services (May 2026), Tables 3 and 4
- CY 2023 PFS final rule, 87 FR 69596–69613 (published November 18, 2022)
- CY 2021 PFS final rule, 85 FR 84572–84574
- CY 2020 PFS final rule, 84 FR 62848–62850
- CMS MLN Matters MM13592 (split or shared visits)
- CMS HCPCS Level II alpha-numeric file, July 2026 release
