Old age as a special period in an individual's life is a relatively new topic in historical research. Interest in this subject has been stirred by the process of population ageing, inevitably affecting all the developed countries and increasingly present in public discourse. Population ageing stems from an increase of longevity but its effects are acutely felt only when it is combined with a decrease of the fertility rate, as a result of which the proportion of old people in the population (however old age is defined) rises to over 20%. In Western Europe the process has been witnessed since the 1960s, being euphemistically called the second demographic transformation. In Poland and other countries of 'the younger Europe' it started in the 1980s and has been much more rapid than in the West. Population ageing leads to a number of economic and social consequences. The article deals with the situation of old people in peasant and gentry families in Poland in the late 18th century. It is based on civil and military census records from the years 1790-92 from the districts of Radziejów and Podgórze in Kuyavia (peasants) and the region of Wielun (gentry). The basic research question concerns the family strategies assumed in view of ageing and their impact on the structure of households. For eighteenth-century peasants in Kuyavia social ageing began when they lost the position of the head of the household. In the case of men this happened quite late, about the age of 70, in the case of women - about the age of 60. In the serfdom system, where contracts and ownership were not legally guaranteed, and the position of elderly people was regulated only by ethical norms not by law, the loss of this position entailed social degradation. Unsurprisingly, peasants tried to avoid it, hanging on to their farms. Men were more successful at that, while women were more quickly and inevitably degraded. The author explored the differences in the structure of peasant and gentry households. In both cases the dominant model was a nuclear family, but the proportion of extended families including lineal ancestors and collateral relatives was different. Among peasants there was a significant proportion of families headed by single mothers; households of more complex structure were uncommon. Gentry households quite often included collateral relatives, usually unmarried or widowed women. The small proportion of households in which widowed mothers lived with their sons' families indicates that widowed gentry women were in a much better position than widowed peasant women. The above-mentioned differences were conditioned by the domination of the production function in peasant households and the lack of ownership guarantees. These factors made the situation of old people in peasant households very difficult. For fear of declassing peasant families get rid of older sons, making them go into service, so that they did not compete with their ageing parents, and replacing them with hired labourers. Widowed men often remarried, which was necessary from the perspective of productivity and helped avoid degradation. Women, who were unable to do that, quickly lost the position of the head of the household. In gentry households the production function was not so prominent and ownership was guaranteed by law, therefore the perspective of ageing was not as disturbing as it was for peasants.