Purpose <p>Cancer survivors and care partners rely on their personal social networks for emotional, informational, instrumental, and belonging support. We examined concordance between expected and received support by assessing how participants’ initial reports of which network members would provide specific types of support aligned with the support they reported receiving over time.</p> Methods <p>At baseline, 32 survivors diagnosed within the past 5 years and their care partners (<i>N</i> = 64) identified 7–20 network members and the types of support each routinely provided. Participants completed repeated interaction surveys over 3 months, describing interactions with network members and the type of support received. Concordance was calculated by comparing baseline expectations to subsequent reports, and associations with participant demographics, network characteristics, and interaction patterns were examined.</p> Results <p>Concordance across all participants and support types was 38%. Individually, average concordance was 57%, with wide variability. Concordance was highest for emotional support and lower for informational and practical support. Higher concordance was associated with more frequent interactions and fewer unhelpful or absent support experiences. No significant associations were found with participant demographics or structural network features.</p> Conclusions <p>Survivors and care partners may be challenged to anticipate how support from their personal networks will unfold over time. Concordance varied by support type and was more closely related to quality and frequency of support interactions than structural network characteristics.</p> Implications for Cancer Survivors <p>Interventions that help survivors and care partners assess their support resources and variation over time may improve alignment between support needs and experiences, enhancing well-being.</p>