HCPCS code G0121: Screening colonoscopy, not high risk2026 Medicare rate & RVUs

Medicare pays $378.43 for G0121 nationally in the office and $165.00 in a hospital or facility. Local office rates run $335.22–$497.73.

Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.

What G0121 covers

G0121 represents a colonoscopy performed for colorectal cancer screening when the patient is not classified as high risk. A gastroenterologist, surgeon, or other qualified practitioner advances a colonoscope through the large bowel to examine the colon for abnormalities. The service may be performed in a physician office or a facility, such as an ambulatory surgery center or hospital outpatient department.

Select G0121 based on the screening indication and the patient’s risk classification, not simply because a colonoscopy occurred. The record should support screening intent and include the procedure findings and extent of examination. CMS assigns a 0-day global period, so same-day preoperative and postoperative care is included. Modifier 53 has separate pricing treatment. When multiple procedures occur in one session, the highest-valued procedure is paid in full and others at 50%. Do not report modifier 50; assistant-at-surgery payment is restricted, and 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 G0121 pays more and less

The same RVUs, adjusted for each area’s costs. Open a locality for its calculation, history and nearby areas.

109 of 109 payment localities

G0121 rates by state

Office rate range in each state. Select a state to see its payment localities.

How the G0121 rate is calculated

Each of G0121’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.

Payment rules and modifiers for G0121

The CMS indicators that decide how G0121 is paid alongside other services.

What modifiers do to the payment

When to use modifier 51

G0121 compared with similar codes

How to choose

G0105Screening colonoscopyHigh-risk individual

Both describe screening colonoscopy, but G0105 is for patients classified as high risk; G0121 is for those not classified as high risk.

G0104Flexible sigmoidoscopyColorectal cancer screening

G0104 reports screening by flexible sigmoidoscopy. G0121 reports screening by colonoscopy, which examines the colon more extensively.

45378ColonoscopyDiagnostic, no tissue removal

G0121 identifies a screening colonoscopy for a patient who is not high risk. CPT 45378 is used for a diagnostic colonoscopy when the clinical indication is diagnostic rather than screening.

Codes related to G0121

Related codes aren’t interchangeable: bill the code that matches the service performed.

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

Open CMS sourceHow we calculate rates