<p>This study modelled the effect of the Social Security and National Insurance (SSNIT) pension scheme on dimensions of retirees’ wellbeing in terms of food, health, finance, and social relations. This study was grounded in the positivist philosophical position and the quantitative approach. A questionnaire was used to gather data from 354 samples from a study population of 4300. Partial least squares structural equation modelling was used to analyse the hypotheses of the study. The study found that the benefits of the SSNIT pension scheme were related inversely and significantly to challenges with the SSNIT pension scheme but were related positively and significantly to the financial wellbeing, food wellbeing, health wellbeing, and social relations wellbeing of retirees. Challenges with the SSNIT pension scheme were found to have a significant relationship with social relations and food wellbeing among retirees, while they had a non-significant relationship with the financial and health wellbeing of retirees. In terms of mediating effect, it was found that challenges with the SSNIT pension scheme significantly mediated the relationship between the benefits of the SSNIT pension scheme and the social relations and food wellbeing of retirees. It was recommended that managers of the SSNIT pension scheme should enhance the benefits associated with pension schemes for retirees by increasing the rate of pension allowance paid to retirees and subsequently revising it upward in relation to the cost of living and national minimum wage.</p>