<p>Cascade testing for Lynch syndrome is critical for the identification of at-risk relatives who may benefit from early detection and risk-reduction strategies. Uptake of cascade testing within families has consistently remained low, and strategies developed to address this have had varying degrees of success. Limited research exists that investigates the perspectives and lived experiences of individuals with or at risk of Lynch syndrome, particularly through rich qualitative methods in the context of cascade testing. This study aimed to explore the lived experience of patients and relatives with cascade testing for Lynch syndrome in the USA. We analyzed qualitative interviews performed with twenty patients either diagnosed with Lynch syndrome, or with a family member diagnosed with Lynch syndrome, using reflexive thematic analysis. Three overarching themes were developed: (1) logistics of disclosure, 2) emotions and beliefs surrounding cascade testing, and 3) reflections on strengths and limitations cascade testing. Genetic counseling was an important component of the cascade testing process; however, participants often described feeling under supported. We propose that alternative models of service provision could help to address this lack of support, and therefore assist in optimizing uptake of cascade testing for Lynch syndrome.</p>