Colorectal Cancer Screening Billing Resources

05 May, 2026

Standard screening colonoscopies must be covered at no cost.

Follow-up colonoscopy after a positive stool test

Medicare, Affordable Care Act, and commercial health insurance plans cover a follow-up colonoscopy after a non-invasive stool-based test is returned with a positive or abnormal result for patients 45 years of age and older. Clinicians can assure patients that if they choose to complete a stool-based testing for colorectal cancer screening, the colonoscopy is fully covered after a positive result.

To code this correctly:

Commercial and Medicaid	Medicare
Add modifier 33	With HCPCS code G0150 or G0121 add modifier KX
For commercial and Medicaid patients, add modifier 33 to each CPT code submitted on the claim. If modifier 33 is not added, the colonoscopy will not be recognized as a screening service and the patient will be inappropriately billed.	Use modifier KX with HCPCS code G0105 or G0121 for screening colonoscopy for patients following a non-invasive stool-based test for patients with Medicare. If polyps are removed, use the appropriate CPT code with modifier PT. Coinsurance applies when polyps are removed

Screening colonoscopy with polyp removal

Select the appropriate code based on the type of removal performed. If multiple polyps/lesions were removed using different techniques, report each method separately.

NOTE: You must add modifier 33 or PT (see below) to identify the polypectomy as a screening service and prevent the patient from being inappropriately billed.

45380	Colonoscopy, flexible; with biopsy, single or multiple
45384	Colonoscopy, flexible; with removal of tumor(s), polyp(s), or other lesion(s) by hot biopsy forceps
45385	Colonoscopy, flexible; with removal of tumor(s), polyp(s), or other lesion(s) by snare technique
45388	Colonoscopy, flexible; with ablation of tumor(s), polyp(s), or other lesion(s) (includes pre- and post-dilation and guide wire passage, when performed)
Modifiers	– Add modifier 33 (preventative services) to each CPT code for *commercial insurance* – Add modifier PT (colorectal cancer screening test; converted to diagnostic test or other procedure) to each CPT code for *Medicare*

Insurance coverage

Commercial insurance	Colonoscopy, bowel prep, sedation, lab work and the hospital or ambulatory surgery center costs where the colonoscopy with polypectomy was performed are covered 100% by health insurance.
Medicare	Through 2026, if a polyp is removed, the patient is responsible for 15% of the cost. From 2027 to 2029 it falls to 10%, and by 2030 it will be covered 100% by Medicare.