Canada vs. U.S. Postal Boundaries: Key Differences for Developers and Analysts

From FSA and LDU in Canada to ZIP and ZIP+4 in the U.S., postal systems differ widely. This guide breaks down those differences and helps data professionals choose the right approach for cross-border analysis and integration.

If you’re building tools or conducting analysis across North America, understanding how postal systems differ between countries is essential.

In Canada, postal codes use a six-character format (e.g., M5V 3L9), where the first three characters form the Forward Sortation Area (FSA) and the last three define the Local Delivery Unit (LDU). In the U.S., ZIP codes follow a five-digit format, optionally extended with ZIP+4.

These differences aren’t just cosmetic. They affect how geographic coverage is modeled. Canadian postal polygons are often more granular and detailed due to dense urban LDUs, while U.S. polygons tend to follow address clusters and population centers.

Aeroview provides both Canadian and U.S. postal boundary datasets, carefully curated and updated using authoritative sources. For cross-border applications — from logistics to franchise planning — understanding these nuances allows developers to maintain consistency while respecting regional formats.

Get the most out of your international analysis by using the right postal polygons for each geography.

Contact Us

Get in Touch

Stay Connected

Subscribe to our newsletter or follow us on social media for insights, updates, and the latest in geospatial technology. We’re here to share valuable information and foster a community dedicated to location-based solutions.

Subscribe for Updates

Stay informed about our latest geospatial services and updates. Join our newsletter for insights tailored to your needs.

By clicking Subscribe, you agree to our Terms and Conditions.