Same-gender couples face unique sexual minority stressors that significantly impact individual and relationship health. This impact may be even greater among same-gender couples living in regions where there are pervasive social and legal biases that affect the lesbian, gay, bisexual, transgender, queer and/or questioning, intersex, asexual, two-spirit (LGBTQIA2S+) community (e.g., south central Appalachia). Brief relationship interventions, like the relationship checkup, are effective at improving relationship health and can be widely disseminated due to the brief and flexible nature of the program. Yet, this program was developed for different-gender couples and, as a result, may lack specific intervention for the unique stressors of same-gender couples. While many skills delivered in relationship interventions, including the relationship checkup, are applicable to all couples, untailored interventions for same-gender couples may result in less impactful outcomes. The present study examined whether the relationship checkup, in its original, unadapted format, is as effective for same-gender couples as it is for different-gender couples. Using a subsample from the larger relationship checkup study (N = 656 couples), the present sample included 64 committed couples (same-gender = 32; different-gender = 32). We used propensity score matching to match different-gender participants to the same-gender participants based on racial minority status, poverty status, marital status, and parenting status. Results revealed that same-gender couples presented similarly to different-gender couples on baseline relationship functioning and changed similarly on all relationship functioning outcomes through 1-month postintervention. Same-gender couples also reported similar degrees of satisfaction with and perceived helpfulness of the relationship checkup. The relationship checkup appears to be equally effective and acceptable for same-gender and different-gender couples. (PsycInfo Database Record (c) 2024 APA, all rights reserved).