From April 2018, HMRC are changing the format of the letter they use to tell their customers their National Insurance (NI) number. This is the letter which is sent automatically to entitled teenagers just before their 16th birthday and to customers who ask for a reminder of their NI number.
The letter is solely to tell or remind HMRC customers of their NI number and let them know what it should be used for. The letter is not proof of someone’s identity and is not proof of their address. The new letter will no longer contain a date of issue as NI numbers do not change.
The new letter will also contain other useful numbers about HMRC services, like Personal Tax Account.