Widowhood becomes increasingly common with advancing age, and spousal bereavement is likely to present additional challenges for adults in very late life. However, previous studies have not considered the potential heterogeneity of the experience of widowhood for different age cohorts. This study provided a novel examination of the experience of social resources during widowhood in the fourth age. Semi-structured interviews were conducted with 20 widowed older men and women in the fourth age, i.e. aged 85 years and older. Participants were asked about their access to, and mobilisation of, social resources during widowhood in the fourth age. The role that these resources play in adjustment to spousal loss was also explored. During this phase, widowhood was associated with diminished social networks and concurrent challenges related to ageing and health which impacted upon support needs and social participation. Despite requiring and receiving increasing levels of social support, participants strove to maximise independence. Males and those widowed during the fourth age were more likely to experience social isolation, loneliness and unwanted informal support. Through the mobilisation of social resources many oldest-old widowed adults continue to lead socially engaged and meaningful lives. The implications of the findings for future policy and practice are discussed, including the need for programmes to promote the continuing independence, self-directedness and social engagement of widowed individuals experiencing advanced ageing.