Collar number

A collar number, also known as a shoulder number, force identification number (FIN) or occasionally as force number (although this can also refer to ID number of a force itself), identifies police officers, police community support officers (PCSO), Special Constables (SC or SPC) and some police staff in UK police forces. Although now displayed on epaulettes (i.e. on the shoulder), it is still commonly referred to as a collar number. Although most forces issue a collar number to all warranted officers, regardless of role, only uniformed officers of the ranks constable and sergeant actually display the numbers.

In most forces it is simply a one- to five-digit number, but in larger forces a letter code (also known as a division call sign) may be added to indicate the officer's base area or unit. In some forces different types of staff (paid ('regular') police officers, special constables, PCSOs and other police staff) are assigned different ranges of numbers, so a person's role can be deduced from the number, but these systems are force specific and there is no national standard.

For the letters shown on riot helmets and the roofs of police vehicles, see Home Office radio callsigns.

In France, the wearing of the collar number is compulsory, save a few exceptions, from 1 January 2014.

Until recently, collar numbers consisted of a number followed by a single letter to indicate the division (e.g. "PC 123A").

In 1914, the force was reorganised into four divisions, each named after its police station:

Moor Lane Police Station was destroyed in the Blitz in 1940, and A Division was abolished and distributed amongst the three remaining divisions. Cloak Lane Police Station was closed down in 1946, and D Division was transferred to the new Wood Street Police Station. The divisions after 1946 therefore stood at:

In 1984, the force was reduced to two territorial divisions, based at Snow Hill Police Station and Bishopsgate Police Station (still B and C Divisions), together with support divisions, and the divisions subsequently stood at:

In February 2009, all the divisions were abolished and the force was divided into directorates (with all patrol officers falling within the new Territorial Policing Directorate, subsequently incorporating certain specialist units and becoming the Uniformed Policing Directorate). All officers' collar numbers were then suffixed by the letters "CP" rather than a divisional letter.

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