The Royal Gibraltar Post Office operates the mail services for this British Overseas Territory, maintaining a single, standardized alphanumeric code. Given the territory's compact size of approximately 6.8 square kilometers, the system is designed to facilitate international routing rather than internal regional sorting. This identifier is essential for maintaining Gibraltar's role as a major Mediterranean hub for shipping and financial services.
Gibraltar uses a single universal Postcode, GX11 1AA. The \"GX11\" prefix was chosen to avoid confusion with existing United Kingdom postcode areas while adhering to the British alphanumeric format.