SE21

London SE postcode area
SE
Postcode area	SE
Postcode area name	London SE
Post towns	1
Postcode districts	30
Postcode sectors	129
Postcodes (live)	20,305
Postcodes (total)	31,852
Statistics as at February 2012

Postcode district boundaries: Bing / Google

The SE (South Eastern) postcode area, also known as the London SE postcode area, is the part of the London post town covering part of south-east London, England. It loosely corresponds to the London Borough of Southwark, London Borough of Lewisham and Royal Borough of Greenwich, the northern part of the London Borough of Croydon, the eastern part of the London Borough of Lambeth, the western part of the London Borough of Bexley and the northwestern part of the London Borough of Bromley.

The postcode area originated in 1857 as the SE district. In 1868 it gained some of the area of the abolished S district, with the rest going to SW. It was divided into numbered districts in 1917, by giving the district closest to London and the location of the head office the suffix "1" and then each district assigned a number alphabetically based on the location of the main office within the district. SE28 is a much later addition carved out of the existing districts SE2 and SE18 in order to accommodate the development of Thamesmead. Unlike in the SW postcode area, where districts are also split into two alphabetical tranches, SE1 is the only head district, and although the numbering begins again at SE19 this is not a head district. The postcode area is part of the London post town. There are no dependent localities used in the postcode area. SE1P is a non-geographic postcode district for PO boxes located in SE1.

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