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Forward sortation area

published · September 16, 2026

A forward sortation area is the first three characters of a Canadian postal code, the part the open postcode data publishes and the part a Canadian address is checked against.

A forward sortation area is the first three characters of a Canadian postal code — the M5V of M5V 3L9 — which names the delivery area the code belongs to; the last three characters, the local delivery unit, narrow it to a block or a building.

What Spaw answers

Canada Post licenses the full code list, and the open data Spaw installs carries the forward sortation areas alone, so the Canadian postcode directory is a prefix directory: a written code is matched on its first three characters, postcode_status reads live when the area exists, and the town, province and centroid are the area's. It is recorded as partial whatever its size, which means a code the directory lacks is never called postcode_not_found. The Dutch four-digit district and the Irish routing key are handled the same way, at four and three characters.

What it is not

It is not the full postcode, and the answer never pretends it is: confirmation.postal_code reads postcode_directory for the area, and nothing about the last three characters is checked beyond the country's pattern.

Related

markdown version: /glossary/forward-sortation-area.md

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