State second pension
State second pension (S2P) is an additional pension option for those who take out the Basic State pension in the UK. It was introduced in 2002 by the actual goverment with the aim to provide some extra benefits for people with average or below-average incomes.
Such an additional scheme existed before, but the state second pension offered a considerable amount of additional payments for low-income UK workers, which was nearly the double of amount of money compared to the the previous Additional Pension scheme. This new pension option also offered a broader cover of pensioners in that sense, that, compared to the previous ones, it was also available for people with long-term illnesses such as diabetes or cancer and with for people with disabilites.
Under this pension scheme, UK workers have to option to pay a part of their National Insurance contribution to a personal pension fund as well, which offers higher benefits and better possibilites for investment. This new pension scheme also offers the option for contracting out up to certain amount of annual contribution payed for the personal fund.
Speaking about the future of state secons pension, there are plans to change it to a flat-rate contribution system instead of salary related.

