Introduction: Long-acting reversible contraception (LARC; including intrauterine devices and implants) is recommended as the first-line contraceptive choice by several professional organizations (eg, American College of Obstetricians and Gynecologists); however, rates of uptake are lower than those of other contraceptive methods. A young woman's social network may influence the decision to use LARC. The purpose of this review was to determine the role of health care providers (HCPs), family, peers, and sexual partner(s) on young women's decisions to initiate LARC.Methods: Several databases (PubMed, CINAHL, and PsycINFO) were searched for articles published between 2000 and 2020 that studied the social network influences of HCPs, family, peers, and sexual partner(s) on LARC initiation among women in the United States aged 18 to 25. A narrative synthesis of the included articles was conducted.Results: Twenty-nine articles met the inclusion criteria (21 qualitative, 6 quantitative, 2 mixed methods). HCPs are an important influence on a young woman's LARC decision-making. Peers and family also have a role but were often sources of negative or inaccurate information. Gaps in the literature were identified, including a lack of data on implant users and a dearth of studies on the role of sexual partner influence; most studies were not guided by theory. Discussion: HCPs are integral to LARC initiation and may be more influential than other social network members. Future research should focus on understanding how social network members interact to result in LARC initiation. Gaining insight into these influences may improve existing interventions or contribute to the development of new interventions and ultimately promote LARC use among young women.