Recently, with the increase in demand, multiple intervention proposals aimed at improving the sexual health of people with intellectual disabilities have emerged. Among them is the SALUDIVERSEX program, which takes a positive approach to sexuality. It has an extended version, consisting of 16 sessions and whose efficacy has already been proven, and a reduced version of 10 sessions. Thus, the present study aimed to test the differential efficacy of the two versions. A total of 208 participants (103 women and 105 men) aged between 19 and 67 years (M = 37.23, SD = 10.66) completed a battery of instruments before and after the intervention. Statistical analyses showed that users who participated in the reduced version of the program presented a significantly higher rate of improvement in their sexual behaviors compared to those who participated in the extended version (Sexual response: β10 = − 0.46 ± 0.19, p = .034; Sex practices: β10 = − 0.52 ± 0.23, p = .037; Use condoms: β10 = − 1.56 ± 0.59, p = .017), as well as a significantly higher decrease in the risk of suffering sexual abuse (β10 = 3.95 ± 0.64, p < .001). However, no statistically significant differences in sexuality knowledge were obtained with respect to the improvement between the two versions (β10 = − 0.09 ± 1.21, p = .94). Meanwhile, the professionals who applied the program found that those who participated in the reduced version, although they presented a significantly greater increase in their knowledge about privacy (β10 = − 0.48 ± 0.08, p < .001), did not improve their concerns about their inappropriate sexual behaviors as much as the users of the extended version (β10 = − 1.35 ± 0.21, p < .001). Thus, although both versions were effective, the reduced version seems to do so to a greater extent and in a shorter time, which makes it the more recommendable option.