Postcode district boundaries:
|Chelmsford postcode area|
|Postcode area name||Chelmsford|
|Statistics as at February 2012|
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.
|Postcode district||Post town||Coverage||Local authority area|
|CM0||SOUTHMINSTER||Southminster, Bradwell, Tillingham, Asheldham, Dengie||Maldon|
|CM1||CHELMSFORD||Chelmsford, Writtle||Chelmsford, Uttlesford|
|CM3||CHELMSFORD||Hatfield Peverel, South Woodham Ferrers, North Fambridge, Cold Norton, Boreham, Maylandsea||Chelmsford, Maldon, Braintree, Uttlesford|
|CM4||INGATESTONE||Blackmore, Fryerning, Ingatestone, Margaretting, Stock||Brentwood, Chelmsford, Epping Forest|
|CM5||ONGAR||Chipping Ongar, High Ongar, Bobbingworth, Moreton, The Lavers, The Rodings||Epping Forest|
|CM6||DUNMOW||Great Dunmow, Felsted||Uttlesford, Chelmsford|
|CM7||BRAINTREE||Braintree, Finchingfield, Great Bardfield||Braintree, Uttlesford|
|CM9||MALDON||Maldon, Tollesbury, Tolleshunt D'Arcy, Tolleshunt Knights||Maldon|
|CM11||BILLERICAY||Billericay (East), Great Burstead||Basildon, Chelmsford|
|CM12||BILLERICAY||Billericay (West), Little Burstead||Basildon, Brentwood|
|CM13||BRENTWOOD||Brentwood, East Horndon, Great Warley, Herongate, Hutton, Ingrave, Little Warley, West Horndon||Brentwood, Basildon, Havering|
|CM14||BRENTWOOD||Brentwood, Warley||Brentwood, Havering|
|CM15||BRENTWOOD||Brentwood, Doddinghurst, Kelvedon Hatch, Mountnessing, Shenfield, Stondon Massey, Pilgrims Hatch||Brentwood|
|CM16||EPPING||Epping, Theydon Bois, North Weald||Epping Forest|
|CM17||HARLOW||Harlow, Old Harlow, Matching, Matching Tye, Matching Green, Church Langley||Harlow, Epping Forest, Uttlesford|
|CM18||HARLOW||Harlow||Harlow, Epping Forest|
|CM19||HARLOW||Harlow, Roydon||Harlow, Epping Forest|
|CM20||HARLOW||Harlow, Gilston||Harlow, East Hertfordshire|
|CM21||SAWBRIDGEWORTH||Sawbridgeworth||East Hertfordshire, Epping Forest|
|CM22||BISHOP'S STORTFORD||Bishop's Stortford, Sheering||Uttlesford, East Hertfordshire, Epping Forest|
|CM23||BISHOP'S STORTFORD||Bishop's Stortford, Thorley, Manuden||East Hertfordshire, Uttlesford|
|CM24||STANSTED||Stansted Mountfitchet, Stansted Airport||Uttlesford|
|CM77||BRAINTREE||Braintree, Great Notley, Rayne||Braintree, Uttlesford|
|CM98||CHELMSFORD||Department for Work and Pensions||non-geographic|
|CM99||CHELMSFORD||Selectapost, International Financial Data Services Group||non-geographic|
- "ONS Postcode Directory Version Notes" (ZIP). National Statistics Postcode Products. Office for National Statistics. February 2012. Table 2. Retrieved 21 April 2012. Coordinates from mean of unit postcode points, "Code-Point Open". OS OpenData. Ordnance Survey. February 2012. Retrieved 21 April 2012.
- Royal Mail, Address Management Guide, (2004)
- "Royal Mail Update 34". Beacon Dodsworth. Retrieved 23 August 2015.
- "Non Geographic Codes" (PDF). Royal Mail Address Management Unit. July 2012. Archived from the original (PDF) on 16 September 2012. Retrieved 20 December 2012.