<p>Problematic engagement in Online Sexual Activities (OSA) has become an increasing concern, given the rapid rise of digital technologies and the consequences of this clinical picture. However, there is still no consensus regarding the nosology and diagnostic criteria of this emerging condition. Although several studies have examined the characteristics and predictors of problematic OSA, few relied on clinical samples or comprehensive diagnostic tools that encompass all existing diagnostic proposals. This exploratory study examined differences between individuals in subclinical (<i>n</i> = 51, 42.5%) and clinical (<i>n</i> = 69, 57.5%) groups of problematic OSA. We evaluated 120 individuals (95.8% men; 72.5% Spanish) aged 21 to 67&#xa0;years (<i>M</i> = 35.98; <i>SD</i> = 9.96) who reported engagement in OSA and were seeking treatment for difficulties controlling sexual impulses. Participants completed an online assessment including clinical criteria drawn from several existing diagnostic frameworks, online and offline sexual behavior, and clinical variables. Individuals in the clinical group spent significantly more time and experienced more orgasms in some OSAs than those in the subclinical group; they also reported higher anxiety, depression, and sexual sensation seeking. Conversely, they spent less time in offline sexual activity. These findings suggest that individuals with clinical patterns of OSA may compensate for lower involvement in offline sexual activities by increasing their engagement in OSA. Furthermore, time spent in sexual intercourse with a steady partner, sexual sensation seeking, trait anxiety, and emotion regulation difficulties emerged as predictors of classification into the clinical group. This study clarifies differences between subclinical and clinical users and may aid in their evaluation and treatment.</p>