Family reactions to coming out can affect the mental health of individuals who disclose their sexual orientation or gender identity. Therefore, it is important to have an appropriate tool to assess them. The Perceived Parental Reactions Scale (PPRS) assessed perceived parental reactions to the disclosure of gay, lesbian, or bisexual sexual orientation by their children. We adapted the PPRS so that it can be answered by any individual belonging to a sexual or gender minority, and can be answered regarding any member of the family, not just parents. A total of 2627 individuals from Spain participated in this study, with a mean age of 31.59 (SD = 11.26). Participants completed the adapted PPRS questionnaire, now named the Family Reaction to Coming Out (FRCO). The FRCO assessed family reactions when disclosing their sexual orientation or gender identity. The majority of participants identified as cisgender men (47.5%) or cisgender women (44.9%), and as gay/lesbian (51.9%). A one‐factor model emerged through exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). The FRCO displayed excellent internal consistency and demonstrated good levels of invariance for participants' gender (male vs female vs nonbinary gender), family member's gender (male vs female), and type of family member (parents vs other family member). Supporting convergent validity, the FRCO has shown a positive correlation with fear of family reaction to coming out. These findings support the validity and reliability of the FRCO tool in assessing the reactions of any family member within the Spanish context.