National Location Code

The National Location Code (NLC) is a four-digit number allocated to every railway station and ticket issuing point in Great Britain for use with the ticketing system on the British railway network. They are used in the issue of tickets and for accounting purposes. They are a subset of the NLCs created by British Rail, which are based on four "main" digits plus two supplementary digits.

NLCs were introduced as a method of accounting for and attributing costs and revenue to railway assets. This quotation is taken from the 14th Edition (January 1987) of the National Location Code listing book, published by the British Railways Board:

"With the widespread use of computers within British Railways and the advent of national computer systems for dealing with payroll compilation, stores recording and accounting, wagon control, traffic data, revenue and expenditure accounting, market and traffic surveys etc., the need for a standard location code became increasingly important. In order to meet this need, the Regions were asked in November 1966 to revise and update the publication then known as the Terminals and Mileage Gazetteer Code. At the same time the opportunity was taken to include all sidings, yards, depots, offices, administrative centres, etc., where there is 'railway' activity. [...] A file was developed based on a six-digit code known as the British Railways National Location Code. This was [first] published on 1 January 1968."

Each six-digit code is split into two parts: the first four digits identify the location of the asset or cost centre, and the final two give more information about the specific asset. The "base" location (including all stations and ticket-issuing locations) has 00 after the first four digits; other two-digit combinations signify other types of asset, with the first four digits indicating the "base" location to which they relate. In ticket issuing, only the first four digits are used. Some examples:

In the 1960s and 1970s, there were various ticket issuing systems in use, some quite localised. Some had simple numerical code structures covering a limited number of stations in the relevant area, but there was no universal coding system to identify stations until the NLC was introduced. NLCs began to appear on certain types of ticket (such as the Southern Region mainstay, the NCR21) almost immediately.

With the introduction of the fully computerised INTIS (Intermediate Ticket Issuing System) in the early 1980s, the four-digit version of the NLC became fully established. INTIS tickets were partly pre-printed, and the station name printed on the ticket had the NLC next to it. The machine printed the codes of the "origin" and "destination" stations on the top line of the ticket.

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