HCPCS code G0104: Flexible sigmoidoscopy, colorectal cancer screening2026 Medicare rate & RVUs in Missouri
Report G0104 for a Medicare colorectal cancer screening performed with a flexible sigmoidoscope to examine the rectum and distal colon.
Medicare pays $189.32–$205.96 for G0104 in the office in Missouri, from Rest of Missouri to Metropolitan St. Louis, MO. Which amount applies depends on the service address.
Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.
Your location
On this page 9 sections
What G0104 covers
G0104 represents a colorectal cancer screening examination using a flexible scope to inspect the rectum and sigmoid colon. It is intended for screening rather than evaluation of symptoms. Gastroenterologists, colorectal surgeons, and other qualified physicians commonly perform the procedure in an outpatient endoscopy center or hospital department. The record should identify the screening purpose, the procedure performed, its findings, and any intervention.
Report one screening procedure, supported by documentation of the clinical indication and examination. The code has a 0-day global period, so routine same-day preoperative and postoperative care is included. When other procedures subject to the CMS multiple-procedure reduction occur in the same session, the highest-valued procedure is paid in full and the others at 50%. Modifier 50 is inappropriate for this single endoscopic service. Medicare does not pay an assistant at surgery for this code; co-surgeons and team surgery are not permitted.
This summary was written with AI assistance from CMS physician fee schedule data and checked against the CMS billing rules shown here. Rates on this page come directly from CMS files.
Where G0104 pays more and less in Missouri
The same RVUs, adjusted for each area’s costs. Open a locality for its calculation, history and nearby areas.
3 payment localities
$189.32 to $205.96
| Payment locality | Office | Facility |
|---|---|---|
| Metropolitan Kansas City, MO | $203.48 | $51.99 |
| Metropolitan St. Louis, MO | $205.96 | $52.37 |
| Rest of Missouri | $189.32 | $50.26 |
How the G0104 rate is calculated
Each of G0104’s three RVUs is multiplied by a geographic index (GPCI) for the payment locality, added up, and multiplied by the conversion factor. Drag the indexes or enter a ZIP to see what moves the rate.
How the rate is built · G0104
RVUs × geographic indexes × conversion factor
Work0.82
0.82 RVUs× 1.000 GPCI
Practice expense5.50
5.50 RVUs× 1.000 GPCI
Malpractice0.11
0.11 RVUs× 1.000 GPCI
Adjusted RVUs
6.4300
Conversion factor
$33.4009
Medicare rate
$214.77
Every GPCI starts at 1.000, the national rate. Enter a ZIP or drag a slider.
Payment rules and modifiers for G0104
The CMS indicators that decide how G0104 is paid alongside other services.
CMS payment indicators · G0104
Flexible sigmoidoscopy, colorectal cancer screening
| Rule | CMS value | What it means |
|---|---|---|
| Global period | 000 | Same-day global: pre- and post-op care on the day of the procedure is included. |
| Multiple procedures | 2 | Standard reduction: highest-valued procedure at 100%, others at 50%. |
| Bilateral (modifier 50) | 0 | The 150% bilateral adjustment doesn’t apply. |
| Assistant at surgery (80/81/82/AS) | 1 | Not paid (statutory restriction). |
| Co-surgeons (62) | 0 | Not permitted. |
| Team surgery (66) | 0 | Not permitted. |
| Professional/technical | 0 | Physician service: no professional/technical split. |
What modifiers do to the payment
Modifier 51 · payment effect
With and without the modifier
G0104 without 51 · national office
$214.77
Flexible sigmoidoscopy, colorectal cancer screening
G0104-51 · Second procedure: 50%
$107.39
When this isn’t the highest-valued procedure in the session, Medicare pays 50% of its fee schedule amount (the highest is paid at 100%).
G0104 compared with similar codes
Compare codes · National
5 codes, side by side
How to choose
- G0105Screening colonoscopyHigh-risk individual
- G0105 describes colorectal screening by colonoscopy for a high-risk patient; G0104 describes screening by flexible sigmoidoscopy.
- G0121Screening colonoscopyNot high risk
- G0121 is the colonoscopy screening code for a patient not classified as high risk. G0104 is the flexible sigmoidoscopy screening code.
- 45330Flexible sigmoidoscopyDiagnostic
- 45330 describes diagnostic flexible sigmoidoscopy. G0104 is for a screening examination, not a procedure prompted by symptoms or a diagnostic indication.
- 45331SigmoidoscopyWith biopsy
- 45331 is a diagnostic flexible sigmoidoscopy code when biopsy is performed; G0104 represents colorectal screening by flexible sigmoidoscopy.
G0104 billing questions
How is G0104 different from a diagnostic flexible sigmoidoscopy?
G0104 is for a colorectal cancer screening examination. Use a diagnostic sigmoidoscopy code, such as 45330, when the procedure is performed to investigate a symptom or other diagnostic indication.
Should modifier 50 be reported?
No. This is a single endoscopic screening service, not a bilateral procedure; modifier 50 is inappropriate.
Is routine same-day evaluation separately included?
Routine same-day preoperative and postoperative care is included under the 0-day global period.
What happens when another procedure is performed in the same session?
Under the CMS multiple-procedure reduction, the highest-valued procedure is paid in full and the other qualifying procedures are paid at 50%.
What documentation supports G0104?
Document the screening purpose, the flexible sigmoidoscopy performed, its findings, and any intervention. If the procedure is diagnostic rather than screening, select the code that represents the diagnostic service.
Where these rates come from
FeeBase calculates base physician payments from CMS work, practice-expense and malpractice RVUs, adjusted by each locality’s geographic indexes and the conversion factor. Services without a published rate are labeled, never given a made-up amount. Amounts are Medicare allowed amounts before claim adjustments: not a patient’s bill or a commercial rate.
CMS RVU26D · effective Oct 1, 2026 through the day before Jan 1, 2027
Show the CMS file lines behind this rate
Fee sheets · Coming soon
Put G0104 and the rest of your codes on one sheet
Your codes at your locality, with payer contracts beside Medicare.
Join the waitlist