What are the billing rules for Z518A?

Use Z518 when the largest polyp excised is 6 mm to 9 mm; only one of Z571, Z518, Z517 or Z516 is payable per patient per day; use the code for the largest polyp excised (S19). A maximum of 2 services of any combination of E720, E520, E519 or E518 (additional polyps) is payable per patient per day (S19). Excision of polyps under 3 mm isn't payable (S19).

What is Z518A often billed with?

The colonoscopy base code, such as Z496, Z498 or Z555, with only one base code per patient per day (S17). E740 (splenic flexure), E741 (hepatic flexure), E747 (cecum) and E705 (terminal ileum) for how far the scope was passed (S18). E520 for each additional 6 to 9 mm polyp, or E720 for additional 3 to 5 mm polyps, to a combined maximum of 2 (S19).

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Billing code

Z518A — Excision of first polyp (6 mm to 9 mm)

Q: What is OHIP billing code Z518A?

Colonoscopic excision of a first polyp 6 mm to 9 mm. One first-polyp code per patient per day, chosen by the largest polyp.

First polyp removal, 6–9 mm

Bill for colonoscopic excision of the first polyp measuring 6 to 9 mm, with the colonoscopy base code.

Watch for: If any polyp removed was larger, bill Z517 or Z516 instead; only one first-polyp code per patient per day.

Provider	Specialist	Assistant	Anaesthetist	Non-anaesthetist
$150.15	$0.00	$0.00	$63.84	$63.84

Code: Z518A
Description: Excision of first polyp (6 mm to 9 mm)
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

Colonoscopic excision of a first polyp 6 mm to 9 mm. One first-polyp code per patient per day, chosen by the largest polyp.

What it covers

Z518 is excision of the first polyp, 6 mm to 9 mm, through the colonoscope. It is billed with the colonoscopy base code for the indication (S16, S17, S19).

Additional polyps of 6 mm to 9 mm are E520. If any polyp removed is larger, the first-polyp code is Z517 (10 to 19 mm) or Z516 (20 to 29 mm); if all are 3 to 5 mm it is Z571 (S19).

Billing rules

Use Z518 when the largest polyp excised is 6 mm to 9 mm; only one of Z571, Z518, Z517 or Z516 is payable per patient per day; use the code for the largest polyp excised (S19).
A maximum of 2 services of any combination of E720, E520, E519 or E518 (additional polyps) is payable per patient per day (S19).
Excision of polyps under 3 mm isn't payable (S19).
Billed with the colonoscopy base code; the base colonoscopy codes already include fulguration, if performed (S19).
No surgical assistant fee is payable (Asst nil) (S19).
Multiple IOPs at the same sitting by the same physician are each claimed in full, with pre- and post-operative care counted once (SP4).
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

The colonoscopy base code, such as Z496, Z498 or Z555, with only one base code per patient per day (S17).
E740 (splenic flexure), E741 (hepatic flexure), E747 (cecum) and E705 (terminal ileum) for how far the scope was passed (S18).
E520 for each additional 6 to 9 mm polyp, or E720 for additional 3 to 5 mm polyps, to a combined maximum of 2 (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).

Related codes: E520, Z571, Z517, Z516, E720, Z498, Z496, Z555

Source: Schedule of Benefits (July 1, 2026), Digestive System Surgical Procedures, Intestines (Except Rectum), Colonoscopy, polyp excision, page S19; base codes S16-S17.

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