American adult adoptees may possess limited information about their biological families and turn to direct-to-consumer personal genomic testing (PGT) for genealogical and medical information. I investigated the motivations and outcomes of adoptees undergoing PGT using data from the Impact of Personal Genomics (PGen) Study. The PGen Study surveyed new 23andMe and Pathway Genomics customers before and 6 months after receiving PGT results. Exploratory analyses compared adoptees’ and non-adoptees’ PGT attitudes, expectations and experiences. I evaluated the association of adoption status with motivations for testing and post-disclosure actions using logistic regression models. Of 1,607 participants, 80 (5%) were adopted. As compared with non-adoptees, adoptees were more likely to cite limited knowledge of family health history (OR = 10.1; 95% CI = 5.7–19.5) and the opportunity to learn genetic disease risks (OR = 2.7; 95% CI = 1.6–4.8) as strong motivations for PGT. Of 922 participants who completed 6-month follow-up, there was no significant association between adoption status and PGT-motivated health-care utilisation or health-behaviour change. PGT allows adoptees to gain otherwise inaccessible information about their genetic disease risks and ancestry, helping them to fill the void of an incomplete family health history.