This part of GOV.UK is being rebuilt – find out what beta means

HMRC internal manual

National Insurance Manual

National Insurance Numbers (NINOs): Roles and Responsibilities: DWP JobcentrePlus

For customers who have not had a NINo, DWP JobcentrePlus handle the first application for a from members of the public. All customers should contact the Jobcentre plus NINO helpline 0345 600 0643.