Medicare Annual Wellness Visit billing: G0402, G0438, G0439.
Three G-codes cover a Medicare patient's entire wellness-visit lifecycle, and each is frequency-locked in a way a commercial preventive exam isn't. Bill the wrong one, or bill the right one a few weeks early, and it doesn't deny for documentation — it denies for timing, on a code that's otherwise correct. This guide covers what each code requires, exactly when it becomes billable, and the same-day scenarios worth doing right rather than leaving on the table.
Key takeaways
- G0402, G0438, and G0439 run in sequence, not in parallel. Welcome-to-Medicare, then initial AWV, then subsequent AWV every year after — billing two of them in the same 12-month window is the single most common denial in this code family.
- The frequency edit is strict to the day, not the calendar year. "At least 11 full months since the last AWV" means a visit scheduled a few weeks early denies as CO-119, even though the same visit two weeks later would have paid clean.
- Advance care planning billed alongside the AWV is genuinely free to the patient — but only with modifier 33, same date, same provider. Miss any one of those three and it reverts to a standard cost-sharing service.
- Z00.00 is the standard diagnosis pointer on all three codes. The AWV isn't adjudicated against a medical-necessity policy the way most Part B services are — it's a statutory benefit — but the claim still needs a valid, billable ICD-10 code on the line.
Three codes, one sequence
Every Medicare beneficiary moves through this code family in a fixed order, and none of the three steps can be skipped or reordered. The costliest mistake in practice isn't picking the wrong code for what the visit was — it's picking the right code for the wrong point in the patient's Part B timeline.
| Code | Visit | When it's billable | Frequency |
|---|---|---|---|
G0402 | Initial Preventive Physical Examination ("Welcome to Medicare") | Only within the first 12 months after the patient's Part B effective date | Once per lifetime |
G0438 | Initial Annual Wellness Visit — establishes the Health Risk Assessment and Personalized Prevention Plan | After 12 months of Part B enrollment have passed, and not within 12 months of a G0402 for the same patient | Once per lifetime |
G0439 | Subsequent Annual Wellness Visit — updates the HRA and prevention plan | At least 11 full months after the last G0438 or G0439 | Once every 12 months thereafter |
None of these three is a hands-on physical exam in the commercial-preventive-code sense, and none accepts a chronic-condition diagnosis as its medical-necessity justification — because there isn't one to satisfy. They're statutory Part B preventive benefits defined by frequency and required content, not services adjudicated against a coverage policy. A direct query of CMS's National and Local Coverage Database turned up no NCD or LCD/Article governing G0402, G0438, or G0439, consistent with that structure: the rules live in CMS's benefit and claims-processing manuals, not a coverage determination.
G0402: the one-time Welcome to Medicare window
G0402 is available exactly once, and only inside a hard window: the first 12 months after the patient's Part B coverage effective date. Miss that window — a patient who delayed enrollment, or simply never scheduled it — and G0402 is gone permanently; the patient moves straight to G0438 once they've completed a full 12 months of Part B enrollment.
The IPPE's seven required elements are more clinical-history-focused than the AWV's, and worth checking against the note before the claim goes out:
- 1Medical and social history — past illness, hospitalizations, operations, allergies, medications/supplements, family history.
- 2Depression/mood-disorder risk factors, using a recognized screening instrument.
- 3Functional ability and level of safety — hearing, ADLs, fall risk, home safety.
- 4Exam: height, weight, BMI, blood pressure, visual acuity screen.
- 5End-of-life planning discussion, if the patient wants one, documented as voluntary.
- 6Education, counseling, and referral based on items 1–5.
- 7A brief written plan for obtaining appropriate screening and preventive services.
A screening EKG hasn't been a required IPPE element since 2009; it's now billed separately (G0403/G0404/G0405), once per lifetime, only when referred out of the IPPE. A medically necessary diagnostic EKG the same day for an actual clinical indication bills under the standard 93000 series with modifier 59, distinct from the wellness visit.
G0438 vs. G0439: what has to be in the note
The initial and subsequent AWV share the same core structure — a Health Risk Assessment, updated history, review of current providers and medications, cognitive impairment assessment, updated Personalized Prevention Plan with a screening schedule — but CMS's required-elements list is more prescriptive for the initial visit.
| Element | G0438 (initial) | G0439 (subsequent) |
|---|---|---|
| Health Risk Assessment | Required, establishes baseline | Required, reviewed and updated |
| Height and BMI | Required | Not explicitly required by CMS, though most practices re-measure as good clinical practice |
| Weight and blood pressure | Required | Required |
| Cognitive impairment assessment | Required | Required |
| Personalized Prevention Plan / screening schedule | Established | Reviewed and updated |
| List of current providers and medications | Compiled | Reviewed and updated |
A note thin on any one of these — most commonly the cognitive assessment, easy to skip when the visit runs long — won't deny the claim outright, but it's the first thing pulled on a payer AWV audit, since the required elements are what distinguish the code from a routine check-in.
The 12-month frequency trap
The timing rule is stricter than most billers expect: "at least 11 full months since the last visit" is measured to the day, not rounded to the calendar month. A subsequent AWV performed even two or three weeks early denies for frequency — not medical necessity, not documentation — and the same is true moving from G0402 to G0438, where the 12-month gap from the Part B effective date is a hard floor.
- Check the exact date of the patient's last AWV before scheduling the next one, not just "last year."
- Confirm the Part B effective date before billing G0402 — it isn't always the patient's first visit to the practice.
- Bill Z00.00 (or Z00.01 with abnormal findings) as the diagnosis pointer on all three codes.
- File an ABN with modifier GA when a patient requests an AWV before the frequency window has elapsed.
- Don't schedule a subsequent AWV by calendar year — use the actual prior date of service plus 11 full months.
- Don't bill G0438 the same year as G0402 assuming the wellness-visit umbrella covers it — the codes run in separate, sequential windows.
- Don't skip the cognitive assessment on a subsequent AWV because it was normal last year; it's required every visit.
- Don't bill without an ABN on file when the visit is genuinely early — a CO-119 with no signed ABN means the practice can't collect from the patient either.
When a CO-119 denial hits with RARC N130 (benefit maximum reached for the time period), the fix almost never involves an appeal — the edit is correct by definition once the visit genuinely happened early. Confirm the actual day gap between the two dates of service, and if it's short even by a week, rebill for the next benefit period rather than appeal a rule that isn't wrong.
Same-day billing: problem visits, G2211, and advance care planning
The AWV doesn't cover treatment of a new or existing problem, which is why modifier 25 comes up so often alongside it — the full decision tree and documentation-separation requirement for that pairing is in our preventive-vs-problem-visit guide, since the same logic applies to a commercial exam or a Medicare AWV. Two AWV-specific scenarios are worth calling out directly.
G2211. The visit-complexity add-on is payable alongside a problem E/M carrying modifier 25 specifically when the same-day service is a Medicare Part B preventive benefit — the AWV, a vaccine administration, or another Part B preventive service. Don't assume the same pairing works against a commercial preventive exam; the exception is built around Medicare's own preventive services.
Advance care planning (99497, +99498). When ACP is furnished as an optional element of the AWV — same date, same provider, billed with modifier 33 on the same claim — Medicare pays 99497 (first 30 minutes) and 99498 (each additional 30 minutes) in full, with the Part B deductible and coinsurance waived. That's a real, no-cost-to-the-patient benefit that's easy to leave unbilled because the conversation happens informally inside the AWV rather than getting logged as its own timed service. Bill it on a different date, without modifier 33, or by a different provider than the one who furnished the AWV, and it reverts to a standard claim with normal cost-sharing.
If the visit includes even a brief conversation about end-of-life wishes or a healthcare proxy, time it and log it separately as 99497 with modifier 33 rather than letting it dissolve into the AWV note. It's fully reimbursed and costs the patient nothing — the only reason it goes unbilled is that nobody wrote down how many minutes it took.
Losing Annual Wellness Visit revenue to frequency denials?
We'll audit your AWV scheduling against actual dates of service and show what's recoverable in ACP and G2211 revenue you're already doing but not billing.
Frequently asked questions
Can we bill G0438 in the same benefit year as G0402?
No. G0438 can't be billed within 12 months of G0402 for the same patient, even though both fall under the Medicare wellness-visit umbrella. G0402 is only available in a patient's first 12 months of Part B enrollment, and G0438 doesn't become billable until a full 12 months after that Part B effective date has passed — the two codes are sequential, not concurrent, and running them the same calendar year denies for frequency.
What ICD-10 code goes on an Annual Wellness Visit claim?
Z00.00 (general adult medical exam without abnormal findings) is the standard diagnosis pointer for G0402, G0438, and G0439, or Z00.01 (with abnormal findings) when the visit turns up something needing follow-up. Medicare doesn't require a medical-necessity diagnosis for the AWV itself — it's a statutory Part B benefit, not a service adjudicated against an LCD — but the claim still needs a valid ICD-10 code, and Z00.00/Z00.01 is what most MACs expect on the wellness-visit line.
Can advance care planning be billed the same day as the AWV at no cost to the patient?
Yes. When 99497 (and its add-on 99498) is furnished as an optional element of the AWV, on the same date, by the same provider, and billed with modifier 33 on the same claim, Medicare pays it in full and waives the Part B deductible and coinsurance the patient would otherwise owe. Bill it without modifier 33, or on a different date than the AWV, and it reverts to a standard Part B service with normal cost-sharing — the modifier is what makes it a no-cost-to-the-patient preventive benefit.
Verify before billing. CPT is a registered trademark of the American Medical Association; codes here are paraphrased, not reproduced from the CPT Professional edition. CPT, HCPCS and ICD-10 codes, coverage policy, and bundling edits change, including annual code-set updates. This page reflects standard industry practice and is provided for general education — it is not a substitute for your own compliance review, your current payer contracts, or the current-year code sets. Confirm requirements against your specific payer mix before submitting claims.