What are the billing rules for A158A?

Billed from the Endocrinology & Metabolism (15) listing by an endocrinologist (A98, GP9). E078 chronic disease assessment premium (+50%) applies only in an office or hospital out-patient clinic (not ED, in-patient or LTC), for an established chronic disease, with one of the GP26 diagnostic codes such as 250 diabetes on the claim (GP25, GP26). Can be billed by video or telephone as comprehensive virtual care with an existing patient-physician relationship; add K300A or K301A, and telephone pays 85% (AJ1, A70).

What is A158A often billed with?

K301A or K300A modality indicator when the visit is done by phone or video (A70). E078 chronic disease assessment premium for an established chronic disease on the GP26 list, office or out-patient clinic only (A98, GP25, GP26).

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Billing code

A158A — Partial Assessment

Q: What is OHIP billing code A158A?

Endocrinology partial assessment: history of the complaint, the needed exam, advice and a record. E078 can be added for an established chronic disease.

Brief endocrinology visit

An endocrinologist bills A158 for a partial assessment: history of the complaint, the needed exam, advice and a record.

Watch for: Add E078 only in an office or out-patient clinic, for an established chronic disease with a listed diagnostic code on the claim.

Provider	Specialist	Assistant	Anaesthetist	Non-anaesthetist
$0.00	$44.75	$0.00	$0.00	$0.00

Code: A158A
Description: Partial Assessment
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

Endocrinology partial assessment: history of the complaint, the needed exam, advice and a record. E078 can be added for an established chronic disease.

What it covers

A158 is the partial assessment in the Endocrinology & Metabolism listing (A98). A partial assessment is the limited service of a history of the presenting complaint, the necessary physical examination, advice to the patient and an appropriate record (GP25).

Billing rules

Billed from the Endocrinology & Metabolism (15) listing by an endocrinologist (A98, GP9).
E078 chronic disease assessment premium (+50%) applies only in an office or hospital out-patient clinic (not ED, in-patient or LTC), for an established chronic disease, with one of the GP26 diagnostic codes such as 250 diabetes on the claim (GP25, GP26).
Can be billed by video or telephone as comprehensive virtual care with an existing patient-physician relationship; add K300A or K301A, and telephone pays 85% (AJ1, A70).
Detention (K001) can only start after 30 minutes of a partial assessment (GP30).

Often billed with

K301A or K300A modality indicator when the visit is done by phone or video (A70).
E078 chronic disease assessment premium for an established chronic disease on the GP26 list, office or out-patient clinic only (A98, GP25, GP26).

Related codes: A154, A153, A151, A155, E078

Source: Schedule of Benefits (July 1, 2026), Consultations and Visits, Endocrinology & Metabolism (15), page A98; General Preamble GP25 (partial assessment, chronic disease assessment premium)

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