Background: The US Department of Veterans Affairs, Department of Defense (VA/DoD) clinical guidelines recommend extended-release naltrexone (XR-NTX) as a treatment option for moderate-to-severe alcohol use disorder (AUD); however, contemporary real-world outcomes related to this guideline are lacking. This retrospective, observational, descriptive study examined treatment patterns and healthcare resource use (HCRU) among veterans with an AUD diagnosis who initiated XR-NTX. Methods: Veterans with incident AUD who initiated XR-NTX between 8/2014 and 11/2018 were identified. Treatment patterns and HCRU were assessed during the 1-year baseline period before and following XR-NTX initiation (the index date). Results: Of the 3665 VA patients (mean [SD] age: 46 [12.5] years; male: 89.7%; White: 76.9%) included in the study, time from AUD diagnosis to XR-NTX initiation was highly variable (mean [range]: 13.6 [0-50.5 months]). Patients received a mean [SD] of 6.8 [6.1] XR-NTX administrations; 44.4% received ⩾6. Mean [SD] time to XR-NTX discontinuation was 93.4 [75.7] days, and 31.3% of discontinuing patients resumed XR-NTX therapy. Of those who received other subsequent medications for AUD, 38.6% (acamprosate) to 47.8% (disulfiram) re-initiated XR-NTX. The proportion of patients with ⩾1 inpatient admissions decreased during follow-up compared with baseline (all-cause: 61.5% to 37.8%; AUD-related: 58.0%-35.4%); with a smaller decrease observed in emergency department (ED) visits. In contrast, more patients had ⩾1 outpatient visits during follow-up (all-cause: 97.5%-99.7%; AUD-related: 84.4%-92.7%). Compared with baseline, mean number of inpatient admissions and ED visits decreased during follow-up, while the number of outpatient visits increased for both all-cause and AUD-related care. Conclusions: Among VA patients with AUD who initiated XR-NTX, we observed reductions in all-cause and AUD-related acute care, and increases in outpatient care. This finding demonstrates a possible transition from acute, inpatient treatment to long-term, outpatient care that may reflect a reduction in disease severity. Additional research is warranted.