<p>Despite the urgent need to improve social connection, practical evidence-based recommendations on how to do so during daily interactions are lacking. One key behavior theorized to facilitate social connection is high-quality listening, yet behavioral evidence is limited. Across two pre-registered studies, we tested whether observed high-quality listening behaviors during conversations between strangers are associated with behavioral and subjective markers of social connection, and whether listening behaviors account for the effectiveness of simple interventions aimed at increasing social connection. Pairs of strangers conversed in either a 10-minute semi-structured conversation (“deep talk”; Study 1) or a brief, “small talk” opportunity (Study 2) following a randomized social connectedness intervention (total <i>N</i> = 646). In Study 1, we found that the frequency of verbal listening behaviors (i.e., verbal validation, follow-up questions) predicted faster conversational response times and other markers of social connection (i.e., 3^rd party observers and self- and partner-reports). Additionally, people randomized to a social connectedness intervention (vs. active control) asked their partner more follow-up questions (i.e., displayed high-quality listening behavior), which in turn, predicted increased social connection. We replicated and extended Study 1 to small talk conversations and found global listening behaviors also predicted behavioral and partner-reported social connection. Verbal listening indicators, however, were less consistently linked to markers of social connection and no evidence emerged that the intervention increased listening behaviors during small talk. Findings suggest observable high-quality listening behaviors may be a promising route to fostering social connection and may enhance the effectiveness of interventions aimed at improving social connection.</p>