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Billing code

A135A — Internal medicine consultation

Internal medicine consultation

An internist bills A135 for a consultation in the office or another general setting at a physician's or nurse practitioner's written request.

Watch for: Put the referrer's billing number on the claim; virtually, it can be done by video only, not telephone.

Code

A135A

Description

Internal medicine consultation

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

Consultation by an internist in the office or another general setting, at the written request of a physician or nurse practitioner.

What it covers

A135 is the Internal Medicine (13) consultation in the General Listings (A129). A consultation is an assessment done at the written request of a physician, nurse practitioner (or a dental surgeon for hospital dental work) who wants your opinion because the case is complex, serious or obscure, or because the patient asked for another opinion. It includes a general, specific or medical specific assessment, a review of relevant data and a written report to the referrer (GP16).

For 75 minutes or more of direct patient contact, see the comprehensive internal medicine consultation A130 (A129).

Billing rules

• Specialists bill from the Consultations and Visits listing for their own Royal College specialty on file with the Ministry, here Internal Medicine (13) (GP9).
• Needs a written, signed request from a physician or nurse practitioner that names you or your specialty, the referrer and their billing number, and the patient and health number. Without it, OHIP pays a lesser assessment (GP16).
• Same patient, same consultant, same diagnosis: one consultation per two consecutive 12-month periods. A second is allowed only for a hospital in-patient or ED patient 12 to 24 months after the first; a clearly unrelated diagnosis allows one every 12 months. Extra consultations pay as an assessment (GP17–GP18).
• A referral you ask for after seeing the patient does not make the visit a consultation; bill the visit you actually provided (GP16).
• Send a written report with your findings, opinion and recommendations to the referrer, and also to the primary care provider when a nurse practitioner referred (GP16).
• Detention (K001) can be added only after 60 minutes of consultation time (GP30–GP31).
• Can be done by video only, not phone, with modality indicator K300A. A video consultation listed in Appendix J itself creates the patient relationship needed for virtual care (AJ2, A66, A70).

Often billed with

• K001 detention, after the first 60 minutes (GP30–GP31).

Common rejections

• ARF: OHIP describes this as 'Missing Physician Referring Number': a consultation claim needs the referring physician's or nurse practitioner's billing number (GP16).
• AT2: OHIP describes this as 'Must include video modality': this code is video-only in Appendix J, so it can't be billed by phone with K301A (AJ2).

Related codes: A130, A435, A136, A133, C135, W235, A120

Source: Schedule of Benefits (July 1, 2026), Consultations and Visits, Internal Medicine (13), page A129. Consultation rules GP16–GP19.

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