Abstract Study question What are the experiences and outcomes of donor conceived adults who are actively searching, open to contact with, and not searching for donor connections? Summary answer Most participants were actively searching or open to contact, of whom 67% had found or been found by a connection; finding/not finding experiences were complex. What is known already There is variation among donor conceived individuals in their interest in donor connections. Individual reasons for searching for connections, and which donor connections are searched for, also vary. Most research studies have focussed on individuals who are actively searching for their donor or donor siblings. Global increases in direct-to-consumer DNA testing and social media participation mean that connections may be made to individuals unaware of their (or their relatives’) involvement with donor conception. These social and technological changes have also increased the chances of donor conceived individuals being contacted without expecting or desiring contact. Study design, size, duration 88 donor conceived adults in the UK participated in an online multi-method survey between January and August 2022. The survey was designed in consultation with the UK’s largest community networks for donor conception families (Donor Conception Network, DCN) and donor conceived people (Donor Conceived Register Registrants’ Panel, DCRRP). It was piloted by five donor conceived people before launch. Participants were recruited with assistance from DCN and DCRRP, via social media, university mailing lists, and snowballing. Participants/materials, setting, methods Participants were mostly female (n = 65, 74%) and sperm donor conceived (n = 79, 90%). 39 participants (44%) were actively searching for their donor connections, 44 participants (50%) were open to contact but not actively searching, and 5 participants (6%) were not searching. Questions were closed (yes/no, rating scale, or multiple choice) and open-ended, addressing experiences of donor conception, searching for connections, and finding or not finding connections. Data were analysed both quantitatively and qualitatively. Main results and the role of chance Quantitative results showed no differences between groups in how they found out about being donor conceived, and no differences between active searchers and those open to contact in whether they had found their donor connections. 59 participants across all groups (active searchers (n = 29, 74%), open to contact (n = 27, 61%), not open to contact (n = 3, 60%)) had found or been found by a donor connection. Active searchers who had found (Median = 3, IQR = 2) were more likely to feel their expectations had been met compared to active searchers who had not found (Median = 3, IQR = 1). (U = 55.00, p = .003) and those open to contact who had not found (Median = 4, IQR = 2) (U = 110.50, p = .001). Qualitative results showed that participants in all groups mentioned identity and belonging, family relationships, and having found connections as reasons for presently searching/not searching. Experiences of finding/not finding donor connections among participants actively searching or open to contact were captured by the theme complexities, and six subthemes: uncertainties in searching and relating; searching as open-ended; different donor connections, different experiences; expectations and realities; searching as catalysing change; and experiences of other donor conceived people. Limitations, reasons for caution Most participants were members of relevant community organisations. As is common in research in this area, the sample were mostly conceived using donor sperm and identified as female. Donor conceived people who are disinterested in donor connections may be unlikely to participate in research on this topic. Wider implications of the findings Assumptions about individual thoughts and experiences of searching for and connecting with donor connections should not be made based on search activity, nor should this determine access to support services. The nature and impact of the search process itself should be considered when developing appropriate mechanisms of support. Trial registration number Not applicable