BackgroundYoung Australian women from culturally and linguistically diverse (CALD) backgrounds are vulnerable to unwanted pregnancy. We aimed to assess whether an online educational video, co-designed with young CALD women, can increase their contraceptive knowledge, preference for and uptake of long-acting reversible contraception (LARC).MethodsOnline advertising was used to recruit young CALD women aged 16–25 years. Participants completed the pre-video survey (S1), watched the 13-min co-designed video, then completed a survey immediately afterwards (S2) and 6 months later (S3). Outcomes were analysed using McNemar tests and multivariate logistic regression.ResultsA total of 160 participants watched the video, completed S1 and S2, and 57% of those completed S3. At S1 only 14% rated their knowledge about every contraceptive method as high. Knowledge improved at S2 for all methods (aOR 3.2, 95% CI 2.0 to 5.0) and LARC (aOR 4.7, 95% CI 2.9 to 7.5). Overall method preference for LARC increased from 2.5% (n=4) at S1 to 51% (n=82) at S2. Likelihood of using a LARC increased at S2 (aOR 3.8, 95% CI 2.6 to 5.6). The overall proportion of participants using a LARC increased from 8% at S1 to 11% at S3; however, this increase was not significant (p=0.7).ConclusionsThe significant increase in knowledge, likelihood of use, and preference for LARC underscores the potential of online video-based contraceptive education to address contraceptive knowledge gaps and challenge misconceptions about LARC held by young women. Combining contraceptive education with supports to LARC access is crucial for empowering young CALD women to make informed contraceptive decisions.