ABSTRACTPrevious studies have reported that patients with borderline personality disorder (BPD) often have negative experiences in psychiatric inpatient care. To address this issue, a novel intervention known as patient‐initiated brief admission (PIBA) has been developed. PIBA offers a constructive approach to crisis management in situations of heightened anxiety, as well as during instances of self‐harm and suicidal ideation. The intervention allows patients to directly contact the psychiatric ward to initiate a brief admission lasting 1–3 days. This easily accessible care option during a crisis has the potential to prevent harm to the patient and reduce the need for prolonged hospital stays. The aim of the present study is to investigate the effects of PIBA on psychiatric care consumption among patients diagnosed with BPD. This retrospective register‐based study includes data from both inpatient and outpatient care registries for patients diagnosed with BPD. Data were extracted from the National Board of Health and Welfare in Sweden. The study period encompasses 2013–2020, with the PIBA intervention occurring between 2016 and 2019. The sample included 107 patients in the PIBA group and 5659 matched controls. Data were analysed using a difference‐in‐differences (DiD) approach through ordinary least squares (OLS) regression and ordinal logistic regression. Throughout the 3‐year follow‐up, both groups exhibited a reduction in the number of days of utilisation of psychiatric inpatient care services. The DiD analysis indicated an additional decrease of 1.5 days at the 6‐month mark for the PIBA group (β = −1.436, SE = 1.531), expanding to 3 days fewer at the 12‐month follow‐up (β = −3.590, SE = 3.546), although not statistically significant. For outpatient care, the PIBA group displayed an increase in the number of visits, averaging to half a visit more every 6 months (β = 0.503, SE = 0.263) compared with the controls. Statistically significant differences were observed for two out of six measurements at the 12‐month (β = 0.960, SE = 0.456) and 18‐month follow‐up period (β = 0.436, SE = 0.219). The PIBA group had a statistically significant lower odds of experiencing extended lengths of inpatient care days after the index date than the controls (OR 0.56, 95% CI: 0.44–0.72). In conclusion, PIBA was associated with a significant reduction in the length of individual hospital stays, but not in the overall number of inpatient care days. PIBA may be linked to a shift from longer inpatient care utilisation to outpatient care utilisation. These findings suggest that PIBA may reduce the risk of prolonged hospitalisations for patients who have access to the intervention. Future research should explore the impact of PIBA on healthcare costs and cost‐effectiveness, both in relation to health care for the individual and cost‐effectiveness in relation to recovery and health.