most of the calculations are done by computer systems and the tables are available only as downloads. In addition, HMRC provide an online National Insurance Calculator. Class 1A Class 1A contributions were introduced from 6 April 1991, and are paid by employers on the value of company cars and certain other benefits in kind provided to their employees and directors, at the standard employer contribution percentage rate for the tax year. Class 1A contributions do not provide any benefit entitlement for individuals. Class 1B Class 1B contributions were introduced on 6 April 1999 and are payable by employers as part of a PAYE Settlement Agreement (an arrangement whereby the employer meets the tax liabilities on certain benefits). Class 1B contributions are paid at the same rate as Class 1A contributions and do not provide any benefit entitlement for individuals. Contribution rates Contribution rates are set for each tax year by the government. The general rates for the tax year 2022/23 between 6 November and 5 April are shown below. For those who qualify for the mariners rates, the employee rates are as shown below and the non-zero employer rates are 0.5% lower than those shown below. Class 2 Class 2 contributions are fixed weekly amounts paid by the self-employed. They are due regardless of trading profits or losses, but those with low earnings can apply for exemption from paying and those on high earnings with liability to either Class 1 or 4 can apply for deferment from paying. As of January 2020, self-employed National Insurance Contributions (NICs) will be categorised as Class 2 when profits are between £6,365 and £8,631.99 a year. If a self-employed worker earns £8,632 or more a year they will be categorised as Class 4. Class 2 contributions are charged at £3.00 per week and are usually paid by direct debit. While the amount is calculated to a weekly figure, they were typically paid monthly or quarterly until 2015. For future years, class 2 is collected as part of the tax self-assessment process. For the most part, unlike Class 1, they do not form part of a qualifying contribution record for contributions-based Jobseekers Allowance, but do count towards Employment and Support Allowance. Class 3 Class 3 contributions are voluntary NICs paid by people wishing to fill a gap in their contributions record which has arisen either by not working or by their earnings being too low.