This study examined whether the association between romantic relationship quality and the conflict tactics people report using in serial arguments varies based on the perceived resolvability of conflicts and three lifespan indicators: age, relationship length, and relationship stage (i.e., dating or married). Participants (N = 584) completed an online survey about their last serial argument. Relationship quality was positively associated with integrative tactics and negatively associated with distributive and avoidant tactics, especially when perceived resolvability was high; in some cases, this pattern was amplified among younger people in shorter or dating relationships. The discussion highlights how the influence of relational quality on conflict tactics is framed by perceived resolvability, and how these processes differ based on the age of individuals, length of relationships, and relationship stage (i.e., dating versus married).