<p>A central issue in the recent reforms of state pensions in Spain has been to increase the proportionality between contributions and benefits along actuarially fair lines. The aim of this paper is to quantify the transfer component of social security retirement pensions, with transfer being understood as the difference between the pension effectively received and that which would be received under a system of actuarial fairness. The analysis is placed within a life-cycle framework, with particular reference to the distributive effects by income level. The results show that, in the past, there was a marked bias in favour of the objective of intergenerational and intragenerational redistribution, to the detriment of the objective of income insurance. This paper examines the factors that determine the final value of the transfer component within the entire Spanish pensions system. </p>