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Billing code

A021A — Advanced Dermatology Consultation

Complex dermatology consultation

A dermatologist bills A021 for a referred consultation on a listed complex condition, such as systemic disease with skin signs or complex psoriasis.

Watch for: The patient must have a listed condition; if relying on the 30-minute criterion, record start and stop times in the chart.

Code

A021A

Description

Advanced Dermatology Consultation

FHO+ basket

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

Effective date

Jun 1, 2025

Termination date

No end date

Explanation

Updated October 26, 2026

Dermatologist consultation for complex skin disease: systemic disease, prurigo nodularis, severe drug reactions, or complex psoriasis or dermatitis.

What it covers

A consultation for the investigation, diagnosis and management of listed conditions that need a dermatologist's expertise: complex systemic disease with skin signs (e.g. sarcoidosis, lupus, dermatomyositis, scleroderma, autoimmune blistering disease, vasculitis, cutaneous lymphoma), prurigo nodularis, or complex systemic drug reactions (drug hypersensitivity syndrome, erythema multiforme major, toxic epidermal necrolysis) (A91).

Also complex psoriasis or complex dermatitis: body surface area over 30%, systemic therapy (e.g. methotrexate, acitretin, cyclosporine, biologics), or a visit needing at least 30 minutes of direct patient contact (A92).

Billing rules

• The patient must have one of the listed conditions (A91, A92).
• The 30-minute criterion excludes time on other separately payable services and non-patient-facing time such as chart, imaging or documentation review (A92).
• If you rely on the 30-minute criterion, record start and stop times in the chart (GP7).
• Keep the referrer's written, signed request in the chart. It must name you or the specialty, the referrer and their billing number, and the patient and health number; otherwise OHIP pays a lesser assessment (GP16).
• Consultation limits apply to time-based consultations too: one per two consecutive 12-month periods for the same diagnosis (GP17, GP18).
• Detention (K001) starts only after 90 minutes of an advanced dermatology consultation (GP30).
• Age premiums apply to specialist consultations and repeat consultations: +30% under 30 days down to +10% for ages 5 to 15 (GP64).
• Virtual care: video only (Appendix J AJ2), with an existing patient relationship and the K300A video indicator; not payable by phone (A66, A70).

Often billed with

• Diagnostic and therapeutic procedures, such as G375/G377 intralesional infiltration, are payable in addition to a consultation or assessment (J3).
• K001 detention after the first 90 minutes (GP30).

Common rejections

• A4D: Invalid specialty for the code; A021 requires the expertise of a specialist in Dermatology (02) (A91, GP9).
• ARF: The claim is missing the referring provider's number. A consultation follows a written request that names the referrer and their billing number (GP16).
• AT2: This code is video only in Appendix J; billing it with the phone indicator K301A is not allowed (AJ2, A70).

Related codes: A025, A026, A020, C025, A027, K001

Source: Schedule of Benefits (July 1, 2026), Consultations and Visits, Dermatology (02), page A91–A92.

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