•The SI SPD group has greater impairment compared with the non-SI SPD group.•Depression and social networking drive the difference between SI and non-SI groups.•Both SI and non-SI SPD groups are impaired in comparison to the HC group. This study compared demographic and clinical features in a sample of 384 participants: healthy controls (HC; n = 166) and individuals with schizotypal personality disorder (SPD) with (n = 50) and without (n = 168) suicidal ideation (SI) to examine specific risk factors for suicidality in SPD. Compared to the non-SI group, the SI group showed significantly greater severity of depression, aggression, impulsivity, affective lability, schizotypal features, poorer social adjustment, and had fewer social contacts. Individuals in the SI group were also more likely to have a history of a suicide attempt and comorbid borderline personality disorder in comparison to the non-SI group. Logistic regression analysis indicated that severity of depression and the number of social contacts drove the difference between the SI and non-SI groups. Compared with both SPD subgroups, the HC group was significantly less depressed, aggressive, impulsive, affectively labile, had fewer schizotypal features, was better socially adjusted, and had more social contacts. This study indicates that overall, the SI group is a more severely impaired group of individuals with SPD compared to the non-SI group. Better educating medical professionals about the diagnosis and management of SPD and its associations with suicidality is warranted.