Billing modifier · CMS claims manual
Modifier 53: a physician service that was stopped.
Modifier 53 indicates discontinuation of physician services. CMS says it is not approved for use on outpatient hospital services. Its best-documented Medicare use is the incomplete colonoscopy, which is billed with modifier 53 and paid at one-half the value of the code’s inputs.
Modifier 53 at a glance
- Modifier
- 53: Discontinued Procedure
- Used on
- Discontinued physician services (not approved for outpatient hospital services)
- Medicare rule
- Incomplete colonoscopy paid at one-half the value of the code inputs since January 1, 2016
- Primary source
- CMS Ch. 4 s.20.6.4; Ch. 12 s.30.1.B
What CMS says
CMS chapter 4, section 20.6.4 states that modifier 53 is used to indicate discontinuation of physician services and is not approved for use for outpatient hospital services. Facilities that stopped a procedure use 73 or 74 (and 52 when anesthesia is not planned) instead. The same section says the elective cancellation of a procedure should not be reported.
Incomplete colonoscopy
Chapter 12, section 30.1.B covers incomplete colonoscopies, for example when the colonoscope cannot be advanced to the cecum or the colon-small intestine anastomosis due to unforeseen circumstances. They are billed with modifier 53 on colonoscopy through stoma code 44388, colonoscopy code 45378 and screening colonoscopy codes G0105 and G0121. Code 44388 is valid with modifier 53 beginning January 1, 2016.
The Medicare physician fee schedule database carries specific values for 44388-53, 45378-53, G0105-53 and G0121-53. Beginning January 1, 2016, Medicare pays the interrupted colonoscopy at a rate calculated using one-half the value of the inputs for the codes. Before that date it was paid at the same rate as a sigmoidoscopy.
Limits
This page covers what the CMS manuals say. The full description of modifier 53 is in the AMA CPT code book, which is licensed and not reproduced here. Commercial payers may apply their own reductions or require documentation; check the payer policy before billing.
Look-alike modifiers
- Modifier 52: Reduced services.
- Modifier 73: Facility procedure stopped before anesthesia.
- HCPCS Level II search: Look up G0105 and G0121.
The full modifier descriptions are in the AMA CPT code book and the HCPCS Level II code set; this page covers only what the CMS claims manuals say about modifier 53.
Sources
- CMS: Medicare Claims Processing Manual, Chapter 4 (Rev. 13799, issued 05-28-26) — section 20.6.4, modifiers 73 and 74 (describes 52 and 53) (retrieved 2026-11-02)
- CMS: Medicare Claims Processing Manual, Chapter 12 (Rev. 13753, issued 05-07-26) — section 30.1.B, incomplete colonoscopies (retrieved 2026-11-02)
Every rule above was read from these CMS pages on November 2, 2026. Payers revise policies and contracts, so confirm anything that affects a claim with the payer or your Medicare Administrative Contractor.
Frequently asked questions
Can a hospital outpatient department use modifier 53?
No. CMS says modifier 53 is not approved for use for outpatient hospital services. Use 73, 74 or 52 as applicable.
How does Medicare pay an incomplete colonoscopy?
It is billed with modifier 53 and, beginning January 1, 2016, paid at a rate calculated using one-half the value of the inputs for the codes.
Should a cancelled elective procedure be reported with modifier 53?
No. CMS says the elective cancellation of a procedure should not be reported.
Not legal, billing or medical advice
This page explains published CMS manual text. It cannot see your claim, your contract or any payer’s policy. Confirm with the payer or your Medicare Administrative Contractor (MAC) before you bill, resubmit or appeal.