Complying with 24 h movement behavior guidelines for pregnant women may prevent pregnancy complications. This single time point, cross-sectional investigation assessed compliance with the 24 h movement behavior guidelines in pregnant women in Saudi Arabia and examined the role of trimester and maternal characteristics. Pregnant women (n = 935; age = 30 ± 5.6 years; first trimester = 24.1%, second trimester = 33.9%, third trimester = 42.0%) self-reported their characteristics (nationality, region, degree, occupation, smoking status, health status, having children, previous birth). The short-version International Physical Activity Questionnaire, Sedentary Behavior Questionnaire, and Pittsburgh Sleep Quality Index Questionnaire measured moderate physical activity (MPA), sedentary behavior (SB), and sleep duration, respectively. Compliance with the 24 h movement behavior guidelines was reported using frequencies and percentages. Prevalence ratios compared the prevalence of compliance by trimester and maternal characteristics. Approximately half of the participants did not comply with MPA or sleep duration guidelines (n = 524, [56.0%] and n = 424, [45.5%], respectively). In contrast, about two-thirds of participants (n = 648, [69.3%]) adhered to the SB guideline. Only 154 (16.5%) participants complied with all 3 24 h movement behavior guidelines. Pregnant women in their second trimester, living in Al-Ahsa Governorate, and currently smoking with a bachelor's degree were the most likely to comply with the guidelines. These findings underscore the need for tailored efforts to promote healthy 24 h movement behavior guidelines for pregnant women in Saudi Arabia, especially early in pregnancy, while accounting for important maternal characteristics.