Colonoscopy Modifier 33 (Preventive)
CPT modifier indicating a preventive service furnished under an ACA-required coverage benefit, waiving patient cost-sharing.
1 min read · Last reviewed May 23, 2026
At a glance
- Category
- Billing
- Primary sources
- 1
- Workspace handoff
- ask d3 →
Where this comes up
This shows up in revenue-cycle work — claim scrubbing, charge entry, posting, A/R follow-up, and month-end close. Billers and practice managers hit this term when reconciling a payment, working a denial queue, or auditing why a claim aged past 60 days.
Full definition
What it is in practice
ACA Section 2713 requires coverage of USPSTF Grade A or B preventive services without cost-sharing. Modifier 33 alerts the payer the service qualifies.
How it shows up in your practice
Append 33 to USPSTF-recommended preventive services. For colorectal cancer screening, modifier 33 (commercial) or PT (Medicare, screening colonoscopy that becomes diagnostic) applies.
Sources
- CMS — Modifier Referencehttps://www.cms.gov/medicare/coding-billing/modifiers
Confirm modifier 33 use in Ask D3
Open ask d3 →Related terms
- BillingAnnual Wellness Visit (AWV)A Medicare-covered preventive visit (G0438 initial, G0439 subsequent) focused on personalized prevention plans.
- BillingModifier PT (Screening Becomes Diagnostic)HCPCS modifier indicating a colorectal cancer screening test was converted to a diagnostic test or therapeutic procedure.
- BillingPreventive ServicesUSPSTF Grade A and B recommendations and ACIP-recommended vaccines that ACA-covered plans must cover without cost-sharing.
D3rx is a healthcare-billing and compliance research aid maintained by D3rx Inc. Articles are drafted by an LLM (Anthropic Claude) against primary HHS, OCR, CMS, eCFR, NIST, and state-regulator publications, and reviewed for restraint and source fidelity by the D3rx team.
Reviewer status: a named credentialed reviewer (CHC, CHPC, or healthcare attorney) is being engaged. Until that engagement is finalized, this page does not claim credentialed review.
Related across the archive
- GlossaryModifier PT (Screening Becomes Diagnostic)HCPCS modifier indicating a colorectal cancer screening test was converted to a diagnostic test or therapeutic procedure.
- GlossaryPreventive ServicesUSPSTF Grade A and B recommendations and ACIP-recommended vaccines that ACA-covered plans must cover without cost-sharing.
- GlossaryAnnual Wellness Visit (AWV)A Medicare-covered preventive visit (G0438 initial, G0439 subsequent) focused on personalized prevention plans.
- GlossaryAnesthesia Modifiers (QY, QK, AD, AA)HCPCS modifiers identifying the anesthesia care team's involvement in a procedure.
- GlossaryModifier 22CPT modifier indicating increased procedural services requiring substantially greater work than usually required.
- GlossaryModifier 24CPT modifier indicating an unrelated E/M service performed by the same provider during a postoperative global period.
- GlossaryModifier 26CPT modifier indicating the professional component of a procedure.
- BillingAWV + Problem Visit Same Day: How to Bill CorrectlyYes, you can bill AWV and a problem visit the same day. Here's how to do it correctly with modifier -25.
This glossary entry is a research aid for billing and compliance staff. It does not provide legal, medical, or financial advice and does not replace counsel. References cited link to primary sources at HHS, OCR, CMS, eCFR, NIST, and the relevant payer or industry body.