National Insurance Number (NINo) data provide information on non-UK nationals at the point they first register for a national insurance number, with data provided by local authority (the place of residence rather than the place of work).
A NINo is generally required for anyone who wants to work or claim benefits, but will exclude many people who are neither working nor claiming benefits, including children. It is therefore not a measure of international migration inflows, because applicants may have come to the UK months or even years before registering and because some migrants will not have NINos. A person can only register once for a NINo, so if they leave the UK for several years this will not be recorded and if they return they will not be included again in the new registrations data.
This guide presents local authority level NINo registration data by nationality (EU2, EU8, EU15, EU Other and non-EU) – see Figure 8.
To learn more about NINo data, please click here.