National Insurance number
The National Insurance number is used as a reference number in the Pay As You Earn system, and also by the self-employed. It is also used in applications for Individual Savings Accounts (ISAs), to check that an individual has opened only one ISA in a tax year.
Universal Credit
Universal Credit is a United Kingdom social security payment that is intended to simplify working-age benefits and to incentivise paid work. It is replacing and combining six means-tested benefits: income-based Employment and Support Allowance, income-based Jobseeker's Allowance, and Income Support; Housing Benefit; and Working Tax Credit and Child Tax Credit.