Associations between higher religiosity and positive marital outcomes are well documented (e.g., Mahoney et al., 1999;Olson et al., 2015), but less attention has been paid to religiosity in unmarried relationships. This study examines associations between religiosity and relationship quality in a sample of individuals in early adulthood (N = 354) who were in serious but unmarried different-sex relationships (mean duration of 4 years). Individuals rated their own religiosity (overall religiousness and attendance) as well as religiosity in their relationship with their partner (dyadic attendance and perception of religious differences with partner). Relationship quality was assessed on three variables: relationship satisfaction, commitment, and negative interaction using three-stage, hierarchical linear regressions. Control variables (age, income, education, relationship duration) were entered in Block 1, individuals' ratings of their own religiosity were entered in Block 2, and then individuals' ratings of dyadic religiosity were entered in Block 3. Results indicated that individual religiosity was only associated with commitment, while dyadic religiosity was associated with all three measures of relationship quality. Greater dyadic attendance and lower religious differences were associated with greater commitment above and beyond both individual religious variables and standard control variables. Having greater religious differences was associated with lower relationship satisfaction and increased negative interaction. Hence, dyadic aspects of religiosity were associated with relationship quality even after controlling for individuals' levels of religiosity. Implications for further research and practice are discussed.