The current study examines the construct of relationship social comparison orientation, which deals with an individual's propensity to compare his or her romantic relationship to that of others' romantic relationships on various dimensions, in both dating and married samples. The study also examines the role of relationship uncertainty and self uncertainty as an inducement or precondition to relationship comparison tendencies in both groups. 204 married individuals were recruited through The University of Iowa employee pool and 270 dating individuals were recruited to participate using the Elementary Psychology research pool. Dating and married individuals completed questionnaires related to relationship social comparison orientation, general social comparison orientation, and personality traits. A subset of married individuals' spouses also completed questionnaires to report as informants on their partners' relationship comparison tendencies, general social comparison orientation and personality. Findings show that married individuals report higher levels of relationship and self certainty and satisfaction than dating individuals. Factor analyses of the Relationship Social Comparison Measure (RSCM; Smith LeBeau & Buckingham, 2008) and relationship comparison tendencies items produced an interpretable and replicable three factor structure, in both samples, of: 1) general relational comparisons, 2) relational comparisons with positive affect and 3) relational comparisons with negative affect. Dating individuals reported more frequent engagement in general relational comparisons and relational comparisons with negative affect. General relational comparisons and negative affect relational comparisons factor scales were significantly, negatively associated with satisfaction in both dating and married samples; in contrast, however, general social comparison orientation was unrelated to satisfaction. Findings, additionally, show significant convergence on self-reported and spouse ratings of personality, in the married sample, for Big 5 traits as well as for relational comparison tendencies and general social comparison orientation. Positive affect relational comparisons were found to have a small positive association with satisfaction, suggesting that some comparison processes are not maladaptive and may serve to bolster relationship functioning.