BACKGROUND Lock To Live (L2L) is a novel web-based decision aid to help people at risk of suicide reduce access to firearms. Researchers have demonstrated that L2L is feasible to use and acceptable to patients, but little is known about how to implement L2L during virtual and in-person contact with healthcare providers. OBJECTIVE The goal of this project was to support implementation and evaluation of L2L during routine primary care and mental health specialty virtual and in-person encounters. METHODS The L2L implementation and evaluation took place at Kaiser Permanente Washington (KPWA), a large regional nonprofit healthcare system. Three dimensions from the RE-AIM model, including Reach, Adoption and Implementation, were selected to inform and evaluate implementation of L2L at KPWA 1/1/2020-12/31/2021. Electronic health record (EHR) data was used to purposefully recruit adult patients, including firearm owners and patients reporting suicidality, to participate in semi-structured interviews. Interview themes were used to facilitate L2L implementation and inform subsequent semi-structured interviews with providers responsible for suicide risk mitigation. Audio-recorded interviews were conducted virtually, transcribed, and coded using a rapid qualitative inquiry approach. Descriptive analysis of EHR data summarized L2L reach and adoption among patients identified at high risk of suicide. RESULTS Initial implementation consisted of updates to the safety planning EHR templates for providers to add a URL and QR code referencing L2L. Recommendations about introducing L2L were subsequently derived from thematic analysis of semi-structured interviews with patients (N=36), which included: 1) “have an open conversation,” 2) “validate their situation,” 3) “share what to expect,” 4) “make it accessible and memorable,” and 5) “walk through the tool.” Providers interviews (N=30) showed a strong preference to have L2L included by default in the EHR-based safety planning template (in contrast to adding it manually). During the two-year observation period, 2739 patients reported prior month suicide attempt planning or intent and had a documented safety plan during the study period, including 745 (27%) who also received L2L. Over four six-month increments of the observation period, adoption of L2L increased substantially-- from 2% to 29% among primary care providers and <1% to 48% among mental health providers. CONCLUSIONS Understanding the value of L2L from users’ perspectives was essential for facilitating implementation and increasing patient reach and provider adoption. Incorporating L2L into the existing system-level EHR-based safety plan template reduced the effort to use L2L and was likely the most impactful implementation strategy. As rising suicide rates galvanize the urgency of prevention, findings from this project, including L2L implementation tools and strategies, will support firearm suicide prevention practices in healthcare nationwide.