What changed in E/M coding on January 1, 2021?

The AMA revised the CPT guidelines for office and outpatient E/M codes 99202-99215, effective January 1, 2021. History and physical exam were removed as level-determining components. The level is now selected by either the level of medical decision making (MDM) or the total time the physician or qualified health professional spends on the encounter that date, whichever the documentation supports.

Can time be used instead of MDM to select an E/M level?

Yes. Total time on the date of the encounter, including both face-to-face and non-face-to-face time personally spent by the physician or qualified health professional that day, is an equally valid basis for code selection. It does not include time spent by clinical staff. Under CMS guidance, the full time threshold must be met; the midpoint rule that applies to some other timed codes does not apply here.

What is the time range for a level-4 established patient visit, CPT 99214?

Under the 2021 revision, 99214 corresponds to 30 to 39 minutes of total time on the date of the encounter, or the MDM level defined as moderate complexity. A visit documented at that time or MDM level and billed at 99213 instead is very likely under-coded relative to the work actually performed.

Does an oral surgery consult typically involve moderate or high complexity MDM?

It depends on the case, not the procedure category. A consult involving review of imaging, coordination with a referring provider, or a patient with comorbidities that raise surgical risk can meet moderate or high complexity on the data and risk elements alone, independent of the final diagnosis. The 2021 rule asks what was actually assessed and weighed that day, not what specialty performed the visit.

Where is the 2021 E/M guidance published?

The American Medical Association publishes the CPT E/M guideline revisions that took effect January 1, 2021. CMS aligned its own billing guidance to the AMA's revised structure, and its guidance is published through the Medicare Learning Network as an Evaluation and Management Services educational resource.

Are You Defaulting Every Consult to 99213? The 2021 E/M Rule Says Check the Level.

Q: What are the three elements of medical decision making under the 2021 rule?

MDM level is set by three elements: the number and complexity of problems addressed at the encounter, the amount and complexity of data reviewed and analyzed, and the patient's risk of complications, morbidity, or mortality from the problem, tests, or treatment. The overall MDM level is generally driven by the highest two of these three elements meeting a given threshold.

Since January 1, 2021, the CPT guidelines for office and outpatient evaluation and management codes, 99202 through 99215, no longer use history and physical exam to set the level. The level is set by medical decision making or by total time on the date of the encounter, whichever the note supports. A level-2 established visit is 10 to 19 minutes of total time. A level-4 is 30 to 39. A level-5 is 40 to 54.

A practice that bills 99213 on nearly every oral surgery consult, regardless of whether the visit involved a straightforward extraction referral or a complicated case with imaging review and comorbidity risk, is very likely leaving real revenue on the table on the more complex visits. Not because the coding is wrong on any individual claim. Because the level was picked out of habit, not out of the MDM or time actually documented that day.

What does the 2021 E/M revision actually change about how a level gets picked?

Before 2021, the level of an E/M visit was built from three components: history, physical exam, and medical decision making, with history and exam doing much of the work of pushing a visit up or down the ladder. The American Medical Association’s revised CPT guidelines, effective January 1, 2021, removed history and exam as level-determining components for the office and outpatient E/M family. The two remaining paths are medical decision making, judged on its own defined criteria, or total time spent by the physician or qualified health professional on the date of the encounter.

This was framed by the AMA as reducing documentation burden, since a clinician no longer has to pad a note with a review of systems just to justify a level. But it also means a note that only documents history and exam, without documenting the complexity of the decision made or the actual time spent, no longer supports any particular level under the current rule. The clinical work has to show up in the MDM or time record, not just in the visit narrative.

What are the three elements of medical decision making, and how do they apply to an oral surgery consult?

MDM level rests on three elements. First, the number and complexity of problems addressed at the encounter, meaning how many distinct issues were evaluated and how complicated each one was. Second, the amount and complexity of data reviewed and analyzed, which for oral surgery can mean imaging interpretation, records from a referring physician, or lab values relevant to surgical risk. Third, the patient’s risk of complications, morbidity, or mortality from the problem itself, from any tests ordered, and from the treatment options considered.

A straightforward extraction referral for a healthy adult with a single clear problem and no data review beyond the referral itself sits at the lower end of this scale. A consult involving a patient on anticoagulants, imaging pulled and interpreted independently, and coordination with the prescribing physician before a surgical decision is made sits meaningfully higher, on data complexity and on risk, independent of what the final procedure turns out to be. The 2021 rule cares about what was actually assessed that visit, not which specialty was doing the assessing.

What is the time-based alternative, and why does the “full time” rule matter?

If time is used instead of MDM, the total time counted is all time personally spent by the physician or qualified health professional on the date of the encounter, both face-to-face and non-face-to-face, and it excludes time spent by clinical staff. CMS guidance is specific that when time is the basis for level selection, the full time threshold for that level must be met; the general CPT rule that allows crossing a timed-service threshold at its midpoint does not apply to E/M level selection.

Established patient code	Total time (2021 revision)
99212	10 to 19 minutes
99213	20 to 29 minutes
99214	30 to 39 minutes
99215	40 to 54 minutes

For new patients, 99202 through 99205 follow the same structure at slightly higher thresholds, from 15 to 29 minutes at the low end up to 60 to 74 minutes at 99205. A visit that runs 35 minutes of documented physician time, with a note that says so, supports 99214 on time alone, independent of the MDM level. If the front desk is billing that same visit at 99213 because that is the default code in the system, the gap between what was documented and what was billed is exactly the exposure worth checking.

Where the mismatch actually shows up in a practice’s own numbers.

The way to find this without guessing is to pull a sample of recent oral surgery consult notes and ask two questions of each one: what does the MDM section actually document, and how much total time does the note support, if time was tracked at all. Then compare that against the code that was actually billed.

A practice where every note supports 99213 and every claim is billed 99213 has no problem. A practice where a third of the notes document 30-plus minutes of total time, or MDM complexity that reads as moderate on data and risk, and every one of those still went out as 99213, has a real and countable gap. That count is specific to the practice’s own charts, not a percentage borrowed from somewhere else, and it is the only honest way to size it.

Why does habit push a note toward the same code every time, regardless of what happened?

A default code is easy precisely because it removes a decision. If 99213 is what the front desk types without thinking, nobody has to open the MDM section of the note and weigh problems addressed against data reviewed against risk, and nobody has to check whether the documented time supports something higher. The default is not dishonest. It is just disconnected from what the 2021 rule actually asks the biller to look at.

This matters more in oral surgery than in a lot of specialties, because the range of what walks through the door on a given day is wide. A single-tooth extraction referral and a consult involving anticoagulant management, imaging review, and coordination with a cardiologist before clearing a patient for surgery can both get scheduled as “oral surgery consult” in the same afternoon. Under the pre-2021 rule, history and exam documentation would often track that difference on their own, almost by accident. Under the current rule, if nobody deliberately checks MDM or time against the code billed, that difference stops showing up in the claim at all, and the higher-complexity visit gets paid at the same rate as the simple one.

Where this comes from

The 2021 E/M revision and its removal of history/exam as level-determining components, the definition of total time and its exclusion of clinical staff time, and the three MDM elements (problems addressed, data reviewed, risk) are documented in the American Medical Association’s CPT E/M guideline changes effective January 1, 2021, as summarized by the American Academy of Family Physicians’ published guide to the same changes. CMS’s alignment of its own billing guidance, including the full-time-threshold rule for time-based selection, is published through the CMS Medicare Learning Network’s Evaluation and Management Services educational resource. Specific time ranges for established-patient codes 99212 through 99215 are drawn from the AMA’s 2021 CPT guideline tables as reported in the AAFP summary.