List of postcode areas in the United Kingdom For the purposes of directing mail, the United
Kingdom is divided by Royal Mail into postcode areas.
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 3 often
combined with these covering the Crown Dependencies of Guernsey, Jersey and Isle of Man.
Subdivision 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.
Scope 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.
Crown dependencies 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.
Defunct postcode areas Glasgow
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.
Dublin Dublin was split into Dublin postal districts
by the Post Office in 1917 at the same time as other major cities in the UK like Liverpool
and Manchester.
After the creation of the Irish Free State (later the Republic of Ireland) the Irish
government did not adopt postcodes; however, the Dublin postal districts remain to this
day and the correct form of address is Dublin 7, etc.
The postcode area D has not been re-used within the UK.
Norwich and Croydon 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.
Non-geographic postcodes GIR
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 addresss.
It uses the notional 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 TSB (BX1 1LT) and the VAT Central Unit of HM Revenue
and Customs (BX5 5AT).
Overseas territories Certain British overseas territories have
postcodes: These were introduced to prevent mail being
sent to the wrong place, e.g., for St Helena to St Helens, Merseyside and Ascension Island
to Asunción, Paraguay, and many on-line companies cannot accept addresses without a postcode.
Such mail is treated as international, not inland, so sufficient postage must be used.