CM11

Chelmsford postcode area
CM
Postcode area	CM
Postcode area name	Chelmsford
Post towns	16
Postcode districts	28
Postcode sectors	103
Postcodes (live)	17,765
Postcodes (total)	25,740
Statistics as at February 2012

Postcode district boundaries: Google

The CM postcode area, also known as the Chelmsford postcode area, is a group of 25 postcode districts in England, which are subdivisions of 16 post towns. These postcode districts cover central Essex (including Chelmsford, Harlow, Brentwood, Billericay, Braintree, Burnham-on-Crouch, Dunmow, Epping, Ingatestone, Maldon, Ongar, Southminster, Stansted and Witham), plus a small part of east Hertfordshire (including Bishop's Stortford and Sawbridgeworth) and a very small part of the London Borough of Havering.

The southern part of the CM7 district for Braintree was recoded to CM77 in 2002.

The Stansted post town (CM24) is entirely surrounded by the Bishop's Stortford post town (CM22 and CM23). The approximate coverage of the postcode districts:

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Wikipedia