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Billing code

Z101A — Abscess, Haematoma I&D (one)

Drain one skin abscess

Bill for incision and drainage of one subcutaneous abscess or haematoma under local anaesthetic.

Watch for: One abscess per Z101; for two or three or more, bill Z173 or Z174 once instead of repeating Z101.

Code

Z101A

Description

Abscess, Haematoma I&D (one)

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

Incision and drainage of one subcutaneous abscess or haematoma under local anaesthetic. Two are Z173, three or more Z174.

What it covers

Z101 is incision and drainage of a single subcutaneous abscess or haematoma under local anaesthetic (M1). Two subcutaneous abscesses are Z173 and three or more Z174; perianal, ischiorectal or pilonidal, and palmar or plantar space abscesses have their own codes (Z104, Z106, Z103) (M1).

As a Z code it is an independent operative procedure, payable in addition to an assessment (GP4). The same drainage under general anaesthetic is Z102 (M1).

Billing rules

• One abscess per Z101; bill Z173 for two and Z174 for three or more rather than more than one Z101 (M1).
• Add E542 when performed outside hospital (M1).
• No surgical assistant fee is payable (Asst nil) (M1). Local anaesthetic you give for your own procedure isn't billed separately (SP5).
• If you did the major pre-operative visit in the previous 12 months, only a minor assessment (GP/FP) or partial assessment (specialist) is payable before the drainage that day; if the decision is made at that day's visit, no other assessment before the IOP (SP4).
• Age premiums apply to surgical procedures for patients under 16 (GP64).
• FHO: in basket (Schedule 2), and a Schedule 2B code, so shadow billing for enrolled patients is 50% of the fee; it also counts toward the Schedule 4 office procedures payment (Agreement p.59 §4.4, p.80, p.87, p.67 §8.7, p.94).

Often billed with

• E542 when the drainage is done in the office or another non-hospital setting (M1).
• A007 intermediate assessment at the visit where the decision to drain is made (GP4, SP4).

Common rejections

• A3H: The line billed more services than OHIP allows. Z101 is for one abscess; for two or three or more, bill Z173 or Z174 once instead of repeating Z101 (M1).
• V23: OHIP questioned the number of services on the line. Check the count, and use Z173 or Z174 when more than one abscess was drained (M1).

Related codes: Z173, Z174, Z102, Z104, Z106, Z103, E542

Source: Schedule of Benefits (July 1, 2026), Integumentary System Surgical Procedures, Skin and Subcutaneous Tissue, Abscess or haematoma - Local anaesthetic, page M1; Surgical Preamble SP4, SP5; FHO Agreement 2026-04 pp.59, 80, 87, 94

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