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Billing code

Z555A — Absence Of Signs Or Symptoms Or Risk Factors, 50 Years Of Age Or Older Sigmoid To Descending Colon

Average-risk screening colonoscopy

Bill for colonoscopy in a patient 50 or older with no signs, symptoms or risk factors.

Watch for: Uninsured within 10 years of a previous Z555, and only one colonoscopy code per patient per day.

Code

Z555A

Description

Absence Of Signs Or Symptoms Or Risk Factors, 50 Years Of Age Or Older Sigmoid To Descending Colon

FHO+ basket

Not in the FHO+ base rate basket (Schedule 2 or 2B).

Effective date

Apr 1, 2026

Termination date

No end date

Explanation

Updated October 26, 2026

Screening colonoscopy for patients 50 or older with no signs, symptoms or risk factors. Uninsured within 10 years of a previous Z555.

What it covers

Z555 is the colonoscopy for a patient aged 50 or older with no signs or symptoms and no risk factors. The fee covers the scope from the sigmoid to the descending colon; further extent is billed with add-ons (S17, S18).

Other indications have their own codes: Z497 after a positive FOBT/FIT or other test, Z499 for an increased-risk family history, Z496 for signs or symptoms (S16, S17).

Billing rules

• Uninsured for the same patient in the 10 years after the previous Z555 (S17).
• A later colonoscopy after a normal Z555, with no intervening signs or symptoms, is Z493 at guideline intervals (S16).
• Only one of Z491, Z492, Z493, Z494, Z495, Z496, Z497, Z498, Z499 or Z555 is payable per patient per day (S17). Z580 flexible sigmoidoscopy isn't payable with it the same day (S15), nor is rigid sigmoidoscopy Z535 (S25).
• Fulguration, if performed, is included (S19). No surgical assistant fee is payable (Asst nil) (S17).
• Before an elective colonoscopy under local anaesthesia and/or I.V. sedation, a preoperative consultation by any physician is payable only when the record shows it was medically necessary (GP18).
• Anaesthesia other than local infiltration, topical anaesthesia or procedural sedation is claimed as E032C (4 basic units plus time units), which replaces the listed basic and time units; GP97 extra units are payable with E032C (GP100). Time units and GP97 extra units aren't payable with Z555C, and E003C isn't payable for anaesthesia for Z555 (S18).
• FHO: Z555A is on the Schedule 4 office-procedures list that counts toward the office procedures special payment when done in the physician's office for enrolled patients (Agreement p.67 §8.7, p.97).
• Marked '#': the fee doesn't include premises, equipment, supplies or staff, which are funded by the hospital budget or ICHSC facility costs; patients can't be charged for them (GP13).

Often billed with

• E740 (splenic flexure), E741 (hepatic flexure), E747 (cecum) and E705 (terminal ileum) for how far the scope was passed (S18).
• Z571, Z518, Z517 or Z516 for the largest polyp removed, with E720, E520, E519 or E518 for up to 2 more (S19).
• A035 consultation (when it is the visit where the decision to scope is made) or A034 partial assessment (when the major pre-operative visit was in the previous 12 months) for a general surgeon (SP4, A107).
• E749 when the colonoscopy is done in a private office; not payable in a hospital or ICHSC (S18, S19).

Related codes: Z493, Z497, Z499, Z496, Z580, E740, E747, Z518

Source: Schedule of Benefits (July 1, 2026), Digestive System Surgical Procedures, Intestines (Except Rectum), Colonoscopy - For diagnosis or ongoing management, page S17; notes S18-S19; GP18; anaesthesia GP100; FHO Agreement 2026-04 Schedule 4 p.97.

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