The number of pupils who have been allocated a unique pupil number (UPN) to date since their inception is not available. The UPN number itself bares no resemblance to the number of UPNs issued. They are based on the local authority number, the school establishment number and a set of randomly generated numbers. UPNs were first introduced in the autumn term of 1999 and cover the maintained schools sector in England.
It was agreed with the Data protection Registrar when the UPN was designed that it would lapse when pupils completed their statutory phase of education. With this in mind, the current policy is that the national pupil database holds the UPN and associated pupil details until that point. After the pupil leaves maintained education the record is retained to enable lifelong learning analyses, but the UPN is removed.