Class 3A is a new voluntary type of National Insurance Contribution (NIC) that is being introduced from 12 October 2015. Broadly, between then and 5 April 2017 certain people will be able to make a contribution to top up their State Pension by up to £25 per week.
Men born before 6 April 1951 and women born before 6 April 1953 will be eligible to make top up payments.
The cost of the contribution will depend on how much extra pension the applicant wants to qualify for (between £1 and £25 per week), and how old they are when they make the contribution. A top up calculator is available on the GOV.uk website at www.gov.uk/state-pension-topup/y
The calculator will help you work out whether it is worthwhile you making Class 3A contributions.