London's Most Famous Postcode: SW1A 1AA (Buckingham Palace)

The postcode SW1A 1AA is the most iconic in the UK—it belongs to Buckingham Palace, the monarch's official London residence.

Breakdown

• SW = South West London postcode area.
• 1 = District (Victoria/Westminster).
• A = Sector.
• 1AA = Unit postcode (specific delivery point: the Palace).

History

Introduced in 1959 as part of the national postcode rollout (Norwich first, 1959; London completed 1974). The SW area covers much of central/west London south of the Thames.

Other Notable SW1A Codes

• SW1A 0AA – House of Commons
• SW1A 0PW – House of Lords
• SW1A 1BA – Clarence House (King's London residence)
• SW1A 2AH – Downing Street (Prime Minister)

London has ~120 postcode districts (E, EC, N, NW, SE, SW, W, WC). SW1A is the only one with "1A" district—reserved for the Crown.