This study examined the relationship between couple relationship satisfaction and the transitivity of ties with family and friends within couples, i.e., the tendency of partners to share friends and family. In this case, transitivity was measured by using three indicators: (1) the proportion of shared friends (friendship network overlap); (2) the frequency of contact that each partner has with their own friends and family as well as those of their partner; and (3) whether social visits to friends and family are made with/without the partner (togetherness). The data were obtained from the Measurement and Observation of Social Attitudes in Switzerland survey, which included 1320 partnered individuals residing in Switzerland. The association between the transitivity of ties with family and friends within couples and couple relationship satisfaction was estimated by using structural equation modeling. According to the results, transitivity was consistently informed by the three selected indicators (i.e., friendship network overlap, frequency, and togetherness), while transitivity positively contributed to couple relationship satisfaction. Moreover, transitivity explains a couple's relationship satisfaction more than the partner's education level and nationality, or the duration of the couple's relationship. By emphasizing the role and importance of joint visits by each member of the couple, this study provides unique insights into the ways in which marital satisfaction can vary.