SO postcode area

Southampton postcode area
SO
Postcode area	SO
Postcode area name	Southampton
Post towns	9
Postcode districts	30
Postcode sectors	179
Postcodes (live)	18,213
Postcodes (total)	38,710
Statistics as at February 2012

Postcode district boundaries: Bing / Google

The SO postcode area, also known as the Southampton postcode area, is a group of 23 postcode districts in England, which are subdivisions of nine post towns. These postcode districts cover south and central Hampshire, including the post towns of Southampton, Winchester, Alresford, Brockenhurst, Eastleigh, Lymington, Lyndhurst, Romsey and ; and other towns, such as Totton, Hythe, Hedge End and Bishop's Waltham.

The area originally had both single and double-digit postcode districts. From the inception of postcodes in Southampton, 'large users' within the SO1 and SO2 postcode areas (which broadly covered the area of the City of Southampton) were allocated SO9 postcodes. In the early 1990s, a shortage of available postcodes occurred due to increased demand. On 1 December 1993 Royal Mail took the step of dividing each of the existing single-digit districts, the numbers of the new subdivisions containing two digits rather than one. For example, the SO1 and SO2 districts were divided into SO14-19. At the same time, ordinary 'geographical' postcodes replaced the SO9 codes. Whilst this created thousands more possible postcode combinations, it resulted in the unusual situation where the centre of the postcode area, Southampton, lacks a district numbered 1. The area is one of only a few in the country where this is the case.

The approximate coverage of the postcode districts:

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