<p>The anatomical relationship between frontal sinus hyperpneumatization and concha bullosa is not well-established, despite their clinical relevance. This study aims to evaluate the prevalence and co-occurrence of these variations in adult patients using CT imaging, as well as to assess their associations with demographic factors, including age and gender. In this cross-sectional study, CT scans of 936 adult Iranian patients were retrospectively analyzed. Frontal sinus hyperpneumatization and concha bullosa were classified as absent, unilateral, or bilateral. Associations with demographic factors were examined using Chi-square and ANOVA tests. Frontal sinus hyperpneumatization was present in 26.5% of patients, while concha bullosa was observed in 51.9%. A significant association was found between the two variations (<i>p</i> = 0.001), with bilateral concha bullosa occurring in 40.5% of patients with bilateral frontal sinus hyperpneumatization. Hyperpneumatization was significantly more prevalent in males (<i>p</i> = 0.001) and younger individuals (<i>p</i> = 0.001). No significant associations were observed between concha bullosa and either gender or age. Frontal sinus hyperpneumatization and concha bullosa frequently co-occur, particularly in bilateral presentations. Recognizing this relationship during preoperative planning may enhance surgical outcomes and reduce intraoperative complications. Our findings contribute to a better understanding of sinonasal anatomical variations and their clinical relevance.</p>