L4 — 20 códigos en 20 localidades (Canadá).
| Código postal | Localidad / Distrito | Provincia / Municipio | Coordenadas |
|---|---|---|---|
| Stouffville | Ontario | 43.9668, -79.2496 | |
| Richmond Hill Southeast | Richmond Hill · Ontario | 43.8582, -79.3985 | |
| Richmond Hill Southwest | Richmond Hill · Ontario | 43.8669, -79.4414 | |
| Richmond Hill North | Richmond Hill · Ontario | 43.9394, -79.4349 | |
| Aurora | Ontario | 44.0001, -79.4663 | |
| Woodbridge North | Woodbridge · Ontario | 43.8432, -79.5644 | |
| Thornhill West | Ontario | 43.8156, -79.4534 | |
| Concord | Ontario | 43.8001, -79.4829 | |
| Woodbridge South | Woodbridge · Ontario | 43.8064, -79.5995 | |
| Barrie North | Barrie · Ontario | 44.4001, -79.6663 | |
| Barrie South | Barrie · Ontario | 44.3572, -79.6929 | |
| Keswick | Ontario | 44.2501, -79.4663 | |
| Midland | Ontario | 44.7501, -79.883 | |
| Richmond Hill Central | Richmond Hill · Ontario | 43.8985, -79.4143 | |
| Mississauga (Malton) | Mississauga · Ontario | 43.7139, -79.6434 | |
| Mississauga (Wildwood) | Mississauga · Ontario | 43.6935, -79.6069 | |
| Mississauga (Matheson / East Rathwood) | Mississauga · Ontario | 43.6413, -79.6296 | |
| Mississauga (East Applewood / East Dixie / NE Lakeview) | Mississauga · Ontario | 43.6178, -79.5786 | |
| Mississauga (West Applewood / West Dixie / NW Lakeview) | Mississauga · Ontario | 43.6028, -79.5929 | |
| Mississauga (West Rathwood / East Hurontario / SE Gateway) | Mississauga · Ontario | 43.6192, -79.6538 |