< Billing codes

Billing code

Z535A — Rigid sigmoidoscopy

Rigid sigmoidoscopy

Bill for sigmoidoscopy with a rigid scope, with or without anoscopy; with biopsy bill Z536.

Watch for: Not billable with screening colonoscopy Z555 or flexible sigmoidoscopy Z580.

Code

Z535A

Description

Rigid sigmoidoscopy

FHO+ basket

Covered by the FHO+ base rate payment for enrolled patients, and shadow billed at 30% (50% for Schedule 2B procedures).

Effective date

Apr 1, 2026

Termination date

No end date

Explanation

Updated October 26, 2026

Sigmoidoscopy with a rigid scope, with or without anoscopy.

What it covers

Z535 is sigmoidoscopy with a rigid scope, with or without anoscopy (S25). With biopsy it is Z536; with decompression of volvulus, Z592 (S25).

Flexible sigmoidoscopy with a 60 cm endoscope is Z580 (S15).

Billing rules

• Not billable with Z555 (colonoscopy) or Z580 (flexible sigmoidoscopy) (S25).
• Add E746 when done outside hospital (S25).
• Z codes are independent operative procedures: if your major pre-operative visit was in the prior 12 months, only a partial assessment is payable before the procedure that day; if the major pre-operative visit is that day, no other assessment is payable before it (SP4).
• Under-16 age premiums (10–30%) apply to surgical procedures in Parts K to Z (GP64).

Often billed with

• E746 when performed outside hospital (S25).

Common rejections

• ADH: OHIP describes this as 'Cannot be billed together': Z535 isn't billable with Z555 or Z580 (S25).

Related codes: Z536, Z592, E746, Z580, Z543, E641

Source: Schedule of Benefits (July 1, 2026), Digestive System Surgical Procedures, Rectum, page S25.

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