Sch 7 para 4
(1) This paragraph applies where a man and a woman are eligible, in such circumstances as may be prescribed, to receive different amounts by way of pension. (2) The difference is permitted if, in prescribed circumstances, it is attributable only to differences between men and women in the retirement benefits to which, in prescribed circumstances, the man and woman are or would be entitled. (3) “Retirement benefits” are benefits under sections 43 to 55 of the Social Security Contributions and Benefits Act 1992 (state retirement pensions) or sections 2 to 12 of the Pensions Act 2014 (state pension) .