POSTCODES of the UK

(selected foreign postcodes at end)

·         UK list

·         UK background

·         Canada

·         Links to other countries' codes and other sites

UK codes list

Background to UK postcodes

The origins of the existing UK Postcode go back as far as the middle of the nineteenth century and arose from the rapid growth of London in the earlier years of that century. So rapid was this that the then Post Office could no longer regard the city as a single town from the viewpoint of sorting mail. Thus the division of London into Postal Districts in 1857-8 effectively divided the capital into smaller and semi-independent postal towns. Sir Rowland Hill. the designer of the first stamp and the man who introduced the uniform postal rate for the whole country, carved up London into eight such Districts. These were denoted by letters representing compass points, such as N (Northern), E (Eastern) and WC (Western Central). Thereafter, all mail from the rest of the country was sent directly to the appropriate office. Between 1864 and 1912, cities such as Liverpool, Manchester, Dublin and Sheffield followed this lead.

Towards the end of the nineteenth century in London — then the world’s largest city — the situation became clogged again. Initially as a war-time labour-saving device, a suffix on the Postal District denoting the Sub-District was introduced formally in 1917. The allocation of the numbering was alphabetical. Thus the Eastern District became E1 whilst Bethnal Green Sub-District became E2 and Bow became E3 [note how the numbers were assigned following the alphabetical order of the names of the sub-districts]. Glasgow followed London’s lead and was the next to introduce such numbering in 1923. Subsequently the original Postal Districts in London became Areas and the Sub-Districts became full Districts in modern terminology.

The next stage in the saga came in the 1950s when the first post-war investigations into the mechanisation of mail sorting were made. It soon became evident that a more sophisticated system of coding was required and that a major exercise would be needed to maximise the use of the new Postcodes by the public. Experiments based on Norwich in 1959 onwards led to the decision to use an alphanumeric (i.e., including both alphabetic and numeric characters) Postcode. Even after much publicity, however, these Postcodes were only used by less than half the senders of mail in the areas concerned. Despite internal doubts about the wisdom of the Postcode within the Post Ofice at that time, a revised version was introduced in Croydon in 1966 and proved more successful. By 1974, the whole of the UK had been allocated Postcodes and Norwich had been recoded. From the viewpoint of Royal Mail, the exercise has been an extended but successful one.      

Converting the Postcode to machine-readable form was originally achieved by an operator receiving the letters one at a time and typing the Postcode on the letter onto a keyboard. This then printed a series of phosphor dots on the envelope to indicate both the Outward and Inward codes. The more modern way is to use optical character readers, which print a form of barcodes on the envelope which is then read by the sorting equipment.[Abridged and adapted from Postcodes, the new Geography by Raper, Rhind and Shepherd (Longman, 1992).

Some aptly chosen UK postcodes

DH99 1NS—National Savings certificate administration, Durham.

GIR 0AA—Girobank headquarters, Bootle.

SAN TA1—Special postcode for children's letters to Santa Claus.

SE1 8UJ—Union Jack servicemen's club.

Canada (included since it is a derivative of the UK system)

@#@ #@# [postfix format, where @ is an alpha character and # is a numeric]

The first letter of a Canadian Postal Code identifies a province, or part of a province:

A = Newfoundland B = Nova Scotia C = Prince Edward Island E = New Brunswick G = eastern Quebec H = Metro Montreal, Quebec J = western Quebec K = eastern Ontario L = central Ontario M = Metro Toronto N = southwestern Ontario P = northern Ontario R = Manitoba S = Saskatchewan T = Alberta V = British Columbia X = Northwest Territories Y = Yukon Territory.

In the second position (the first number), a 0 indicates that the postal code is for a whole post office, usually indicated for rural communities. The 6th character (last number) is also usually a 0 in such cases (as in L0M 1S0). All addresses for the community have that postal code, whether these are rural routes, postal boxes or in some cases, smaller towns with letter carrier routes. Other numbers for the second position indicate the postal code is in a larger urban community with letter carrier service. The postal code is thus precise enough to identify street blocks, particular rural routes or groups of postal boxes. Postal Codes are always separated into two blocks of three characters. The first three characters are the Forward Sortation Area (FSA), an "area code" to identify a district. The last three characters thus identify the block, postal box set, or post office within the FSA.

Some special FSAs: K1A is for federal government activities in Ottawa; M7A represents the Ontario provincial government, G1A represents the Quebec provincial government. One code document indicated that A9W, A9X and A9Z were used as test FSAs (these would not be for actual locations; likely to check equipment, etc). H0H 0H0 is a special code used to write to "Santa Claus". This is a special promotion prior to the Christmas holidays.

The letters D, F, I, O, Q and U are never used in a Canadian Postal Code, due to potential conflicts with other letters or numbers. Canada Post Corporation announced plans to extend the Postal Code by adding extra numeric digits. This is intended to identify the exact street number on a block. or the particular postal box. As of this writing, none of these extended postal codes have been announced. [ Extract from Postcode formats of the world, a website now defunct.]

Links

·         The official UK postcode lookup site is at http://www.royalmail.co.uk/paf/

·         Excellent resource on UK postcodes at http://www.brainstorm.co.uk/public/utils/postcodes.html

·         Link to German postcodes, which converts old-style postcodes to current format. [now defunct]

·         Link to US Zip Code search.

·         Postcode formats of the world. [now defunct]

This survey is not exhaustive by any stretch of the imagination, so amendments and additions will be welcomed gratefully by the compiler. Thanks!

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