Adrenal incidentalomas (AI) are an escalating clinical issue due to the increasing use of imaging techniques. Occasional patients with AIs have been reported who have subsequently been diagnosed with congenital adrenal hyperplasia (CAH) due to CYP21A2 mutations (21-hydroxylase deficiency) or carrier status. The objective of this investigation was to describe a larger cohort of patients with AI suspected to be caused by 21-hydroxylase deficiency or carrier status. All patients with AI and suspected CYP21A2 mutations during the last decade at a single center in Stockholm, Sweden, were included. Nine patients were identified (54 ± 19-year-old at presentation). Two-thirds were females and two-thirds were from Sweden, while one-third was from the Middle East. Almost all (8/9) had children, but two had experienced fertility problems. Four of six women had symptoms of hyperandrogenism, and three had previously been diagnosed with polycystic ovary syndrome. The majority (7/9) had multiple AIs. In two cases, the initial suspicion had been adrenal cortical cancer, but increased urinary pregnanetriol had lead to the diagnosis of CAH. Basal serum 17-hydroxyprogesterone was 10 (1.75-338) nmol/L. Seven was diagnosed with CAH (six non-classic, one simple virilizing). Two patients were considered to be carriers. However, in four patients, no CYP21A2 mutation was found and thus no confirmation of the diagnosis could be achieved. Patient presented with multiple AIs with hyperandrogenism or a Middle East origin screening for CAH or carrier status may be indicated.