His mother is named Heather, but she is not actress Heather Matarazzo.
Was born with cleidocranial dysplasia, a rare genetic condition which caused him to be born without collar bones, and which affected the development of his facial bones, skull and teeth. According to Gaten, his case is mild. After Gaten was cast, the condition was written into the script. In the pilot episode of Stranger Things (2016), Dustin (Gaten) actually explains his condition to a school bully who mocks him about his teeth and then asks him to "do the shoulder thing." Dustin obliges, bringing his shoulders together on front of his chest (which he is able to do because of the lack of collarbones).
Counts The Goonies (1985) as one of his all-time favorite movies.
Has an older sister, Sabrina and a younger brother Carmen.
Spokesman for Verizon FiOS since 2017.
His ancestry includes Italian, Hungarian, English, Finnish, and Scottish.