The data presented here provide one of the first large-scale insights on adult preferences for confidentiality and consent with regards to medical decision-making for minors. We collected data on these preferences through 12 hypothetical scenario’s that were presented, for which each participant had to indicate if they would (not) follow the minor’s preferences. Data regarding family communication, relationship quality, and sociodemographic characteristics were also collected. The data were collected through an online survey in September and October 2020, which yielded responses from 1,000 Belgian and 1,000 Dutch participants between 35 and 55 years of age. We selected this age range because it increased the chances that they had a child near the age of the fictional minor in the hypothetical cases. These data can be of interest for family researchers and/or health workers who want to explore adults’ perceptions regarding confidentiality and consent among minors. ...