Emerging adults lack many basic financial capabilities. To avoid conflict that may come from these deficiencies, some emerging adults may financially deceive their romantic partner. However, little is known about financial deception in emerging adult romantic relationships. Through the lenses of two theoretical frameworks, we test whether financial deception intervenes the associations of couple financial communication, financial socialization, and similarity of financial values with romantic relationship flourishing in a sample of 1,950 U.S. emerging adults. Results indicate that couple financial communication, similarity of financial values, and financial socialization may contribute positively toward romantic relationship flourishing. However, financial socialization and financial deception may contribute negatively toward romantic relationship flourishing. Findings are discussed in light of the theoretical frameworks utilized, implications for clinicians and educators are identified, and directions for future research are presented. In summary, being less than fully honest about finances may have implications for emerging adults in romantic relationships.