The list of postcode areas in the United Kingdom is a tabulation of the postcode areas used by Royal Mail for the purposes of directing mail within the United Kingdom. The postcode area is the largest geographical unit used and forms the initial characters of the alphanumeric UK postcode.  There are currently 121 geographic postcode areas in use in the UK and a further three often combined with these covering the Crown Dependencies of Guernsey, Jersey and Isle of Man.
Each postcode area is further divided into post towns and postcode districts.  There are on average 20 postcode districts to a postcode area.  The London post town is instead divided into several postcode areas. 
The single or pair of letters chosen for postcode areas are generally intended as a mnemonic for the places served.  Postcode areas, post towns and postcode districts do not follow political boundaries and usually serve much larger areas than the place names with which they are associated. For example, within the PA postcode area the PA1 and PA78 postcode districts are 140 miles apart; and the eight postcode areas of the London post town cover only 40% of Greater London.  The remainder of its area is covered by sections of twelve adjoining postcode areas: EN, IG, RM, DA, BR, TN, CR, SM, KT, TW, HA and UB. 
|Postcode area||Postcode area name  ||Code formation||Number of postcode districts within area|
|AB||Aberdeen||33 (Highest number 56)|
|B||Birmingham||79 (Highest number 98)|
|BA||Bath||19 (Highest number 22)|
|BB||Blackburn||13 (Highest number 18)|
|BD||Bradford||27 (Highest number 99)|
|BH||Bournemouth||26 (Highest number 31)|
|BL||Bolton||10 (Highest number 9)|
|BN||Brighton||30 (Highest number 45)|
|BS||Bristol||37 (Highest number 49)|
|BT||Belfast||81 (Highest number 94)|
|CB||Cambridge||16 (Highest number 25)|
|CF||Cardiff||35 (Highest number 83)|
|CH||Chester||37 (Highest number 66)|
|CM||Chelmsford||25 (Highest number 77)|
|CV||Coventry||24 (Highest number 47)|
|DE||Derby||23 (Highest number 75)|
|DG||Dumfries ||Dumfries and Galloway||15 (Highest number 16)|
|DN||Doncaster||32 (Highest number 41)|
|E||East London||20 (Includes E1W)|
|EC||East Central London||23 (Layout for EC is different, e.g.: EC2R 8AH, highest number 4/4Y)|
|EH||Edinburgh||54 (Highest number 55)|
|EX||Exeter||33 (Highest number 39)|
|FY||Blackpool ||The Fylde||8|
|G||Glasgow||52 (Highest number 84)|
|GL||Gloucester||27 (Highest number 56)|
|GU||Guildford||38 (Highest number 52)|
|HA||Harrow||10 (Highest number 9)|
|HP||Hemel Hempstead||24 (Highest number 27)|
|IG||Ilford||Possibly Ilford and Barking||11|
|IV||Inverness||52 (Highest number 63)|
|KA||Kilmarnock||Possibly Kilmarnock and Ayr or Kilmarnock||30|
|KT||Kingston upon Thames||24|
|KW||Kirkwall||16 (Highest number 17)|
|LD||Llandrindod Wells ||8|
|LE||Leicester||21 (Highest number 67)|
|LL||Llandudno||67 (Highest number 78)|
|M||Manchester||43 (Highest number 90)|
|MK||Milton Keynes||26 (Highest number 46)|
|N||North London||23 (Includes N1C, Highest number 22)|
|NE||Newcastle upon Tyne  ||61 (Highest number 71)|
|NG||Nottingham||29 (Highest number 34)|
|NN||Northampton||19 (Highest number 29)|
|NP||Newport||18 (Highest number 44)|
|NW||North West London||11|
|OX||Oxford||27 (Highest number 49)|
|PA||Paisley||67 (Highest number 80)|
|PH||Perth||43 (Highest number 50)|
|PO||Portsmouth||34 (Highest number 41)|
|PR||Preston||11 (Highest number 26)|
|RG||Reading||30 (Highest number 45)|
|S||Sheffield||45 (Highest number 81)|
|SA||Swansea||51 (Highest number 73)|
|SE||South East London||28|
|SL||Slough||10 (Highest number 9)|
|SM||Sutton ||Possibly Sutton and Morden, the two post towns that are within the SM area ||7|
|SN||Swindon||18 (Highest number 26)|
|SO||Southampton||23 (Highest number 53)|
|SW||South West London||27 (SW1 is represented by SW1A, -E, -H, -P, -V, -W, -X & -Y, Highest number 20)|
|TN||Tunbridge Wells ||40|
|W||West London||26 (W1 is split into W1A through W1D, -F to -H, -J, -K, -S through -U and -W, highest number 14)|
|WC||West Central London||14 (WC1 is split into eight, WC2 is split into six, highest number 2/2R)|
|WD||Watford||11 (Highest number 25)|
|YO||York||29 (Highest number 47)|
The Crown dependencies (which are not part of the United Kingdom) did not introduce postcodes until later, but use a similar coding scheme. They are separate postal authorities. 
|Postcode area||Postcode area name|
|IM||Isle of Man|
Glasgow, like London, was divided into compass districts: C, W, NW, N, E, SE, S, SW. When postcodes were introduced, these were mapped into the new G postcode: C1 became G1, W1 became G11, N1 became G21, E1 became G31, S1 became G41, SW1 became G51, and so on. As NW and SE had never been subdivided they became G20 and G40 respectively.
Norwich and Croydon were used for a postcode experiment in the late 1960s, which was replaced by the current system. The format was of the form NOR or CRO followed by two numbers and a letter, e.g. NOR 07A. They were later changed to CR0 (digit '0') and NR1.
When Ireland was a part of the United Kingdom of Great Britain and Ireland a postal district system was introduced in 1917 by the UK government. The letter D was assigned to Dublin. Upon the establishment of the Irish Free State and later, the Republic of Ireland, the Irish government retained the designation and today it forms part of the Eircode system. Since Irish independence, D has never been reassigned as a postcode area in the UK. Modern postcodes throughout the Republic of Ireland take a slightly different form from UK postcodes and are specific to individual addresses.
A number of non-geographic postcode sectors are also contained within geographic postcode areas.
GIR 0AA is a postcode created for Girobank in Bootle. It remained in use by its successors when Girobank was taken over by Alliance & Leicester and subsequently by Santander UK.
The BF postcode area was introduced in 2012 to provide optional postcodes for British Forces Post Office addresses, for consistency with the layout of other UK addresses. It uses the national non-geographic post town "BFPO" and, as of 2012, the postcode district "BF1".
The non-geographic postcode area BX has been introduced for addresses which do not include a locality: this allows large organisations long-term flexibility as to where they receive their mail. This postcode area is used by Lloyds Banking Group (BX1 1LT), HSBC (BX8 0HB) and parts of the HM Revenue and Customs like VAT Central Unit (BX5 5AT) and Pay as You Earn (BX9 1AS). Lloyds Bank also use BX4. After splitting from Lloyds, TSB Bank uses BX4 7SB, the latter part of which, when written, looks similar to "TSB".
The non-geographic postcode area XX is used by online retailers for returns by Royal Mail, and for COVID-19 test samples.
|Amazon||XX10 1DD (Scottish Distribution Centre)  |
XX40 2PP (National Distribution Centre)
XX10 1ZZ (Yorkshire Distribution Centre)
XX50 1DD (Scottish Distribution Centre)
XX50 9SS (Scottish Distribution Centre)
XX30 1FF (South West Distribution Centre)
XX60 1XX (Princess Royal Distribution Centre)
|BT Group||XX10 1BT|
|John Lewis||XX10 1EE|
|Marks & Spencer||XX10 1SS|
|HP / Cycleon Retail Returns||XX40 1EH|
XX40 2HH (Toner Cartridge Recycling)
|Monsoon Accessorize||XX40 1EP|
|Biocentre (COVID-19 testing)||XX40 4FL|
|AstraZeneca (COVID-19 testing)||XX40 8AZ|
|Biocentre (COVID-19 testing) Scotland||XX50 5FL|
Certain British Overseas Territories introduced single postal codes for their territory or major sub-sections of it. These are not UK postcodes, even though many are formatted in a similar fashion:
|Saint Helena, Ascension and Tristan da Cunha:|
|British Indian Ocean Territory||BBND 1ZZ|
|British Antarctic Territory||BIQQ 1ZZ|
|Falkland Islands||FIQQ 1ZZ |
|Pitcairn Islands||PCRN 1ZZ|
|South Georgia and the South Sandwich Islands||SIQQ 1ZZ|
|Turks and Caicos Islands||TKCA 1ZZ |
Other overseas territories have introduced their own more extensive postcode systems:
|Overseas Territory||Further information|
|Bermuda||Postal codes in Bermuda|
|Cayman Islands||Postal codes in the Cayman Islands|
|British Virgin Islands||Postal codes in the British Virgin Islands|
|Montserrat||Postal codes in Montserrat|
Civilian residential and business addresses in Akrotiri and Dhekelia are served by Cyprus Postal Services and use Cypriot postal codes.
Mail to Overseas Territories is treated as international if posted in the UK.
A postal code is a series of letters or digits or both, sometimes including spaces or punctuation, included in a postal address for the purpose of sorting mail.
Postal codes used in the United Kingdom, British Overseas Territories and Crown dependencies are known as postcodes. They are alphanumeric and were adopted nationally between 11 October 1959 and 1974, having been devised by the General Post Office. A full postcode is known as a "postcode unit" and designates an area with several addresses or a single major delivery point.
The London postal district is the area in England of 241 square miles (620 km2) to which mail addressed to the London post town is delivered. The General Post Office under the control of the Postmaster General directed Sir Rowland Hill to devise the area in 1856 and throughout its history it has been subject to reorganisation and division into increasingly smaller postal units, with the early loss of two compass points and a minor retraction in 1866. It was integrated by the Post Office into the national postcode system of the United Kingdom during the early 1970s and corresponds to the E, EC, N, NW, SE, SW, W and WC postcode areas. The postal district has also been known as the London postal area. The County of London was much smaller, at 117 square miles (300 km2), but Greater London is much larger at 607 square miles (1,570 km2).
The W postcode area, also known as the London W postcode area is a group of postcode districts covering part of central and part of West London, England. The area originates from the Western (W1) and Paddington (W2-14) districts of the London postal district. This area covers 35 postcode districts and around 18,554 live postcodes.
The E (Eastern) postcode area, also known as the London E postcode area, is the part of the London post town covering much of east London, England. It borders the N postcode area to the west, both north of the tidal Thames. Since closure of the East London mail centre its mail is sorted at Romford Mail Centre together with IG and RM postcode areas.
The IG postcode area, also known as the Ilford postcode area, is a group of eleven postcode districts in England, within six post towns. These cover parts of eastern Greater London and south-west Essex. Inward mail for the area is sorted, along with mail for the E and RM postcode areas, at the Romford Mail Centre.
The SM postcode area, also known as the Sutton postcode area, is a group of seven postcode districts in England, within five post towns. These cover part of south-west London, as well as a small part of north Surrey.
A "postal address" in Ireland is a place of delivery defined by Irish Standard (IS) EN 14142-1:2011 and serviced by the universal service provider, An Post. Its addressing guides comply with the guidelines of the Universal Postal Union (UPU), the United Nations-affiliated body responsible for promoting standards in the postal industry, across the world.
The KA postcode area, also known as the Kilmarnock postcode area, is a group of 30 postcode districts in south-west Scotland, within 23 post towns. These cover East Ayrshire, North Ayrshire and South Ayrshire.
The DN postcode area, also known as the Doncaster postcode area, is a group of 32 postcode districts in England, which are subdivisions of 13 post towns. These cover eastern South Yorkshire, north Lincolnshire, small parts of Nottinghamshire and the East Riding of Yorkshire, and a very small part of North Yorkshire.
The S postcode area, also known as the Sheffield postcode area, is a group of postcode districts in England, which are subdivisions of eight post towns. These cover most of South Yorkshire, parts of north Derbyshire and north-west Nottinghamshire, plus a small part of West Yorkshire.
The NW postcode area, also known as the London NW postcode area, is a group of 13 postcode districts covering around 13,895 live postcodes within part of northwest London, England. It is the successor of the NW sector, originally created as part of the London postal district in 1856.
The SE postcode area covers a broad radial swathe of the south-east of the London post town from the Albert Embankment to West Heath and the nearest edges of Sidcup and Selhurst. It loosely corresponds to the boroughs of Southwark, Lewisham and Greenwich plus indicated parts of the boroughs of Croydon (north), Lambeth (east), Bexley (west) and Bromley.
The NE postcode area, also known as the Newcastle upon Tyne postcode area, is a group of 61 postcode districts in north-east England covering 34 post towns. These cover most of Tyne and Wear and Northumberland, plus a very small part of northern County Durham.
The PL postcode area, also known as the Plymouth postcode area, is a group of 35 postcode districts in South West England, within 25 post towns. These cover west Devon and east Cornwall.
The N (Northern) postcode area, also known as the London N postcode area, is the part of the London post town covering part of North London, England. It is a group of 25 postcode districts which covers around 17,429 live postcodes.
The G postcode area, also known as the Glasgow postcode area, is a group of postcode districts in central Scotland, within five post towns. These districts are primarily centered on Glasgow itself, and West Dunbartonshire, plus parts of the council areas of Argyll and Bute, East Dunbartonshire, North Lanarkshire, South Lanarkshire, East Renfrewshire and Stirling.
The SW postcode area, also known as the London SW postcode area, is a group of 20 postcode districts within the London post town in England. The area comprises the South Western operational district and the Battersea operational district, and is the only area within the London post town to lie on both sides of the River Thames.
Postcode area boundaries: