Introduction: Sexting is a new way to explore sexuality among adolescents that can be associated with bullying behaviors. Previous studies have focused on peer-victimization but relationships between bullying and different forms of sexting have not been explored. This study evaluates the reciprocal relationships between the perpetration of traditional bullying, cyberbullying, and four forms of sexting (sending, receiving, third-party forwarding, and receiving sexts via an intermediary). Methods: The sample consisted of 1736 Spanish High School students (46.3% female; M age = 13.60, SD = 1.25). Four direct questions were used to assess sexting, the EBIPQ to measure traditional bullying and the ECIPQ to evaluate cyberbullying. These measures were completed twice, four months apart. A cross-lagged panel analysis evaluated the reciprocal associations of all study measures. Results: Traditional bullying and cyberbullying were positively, reciprocally associated with each other. Generally, those young people who engaged in sexting at T1 were more likely to report engaging in sexting at T2. Third-party forwarding of sexts (forwarding on sexts which have been sent to a young person by others) displays clear relationships with bullying. Young people who reported using traditional bullying behaviours at T1 were more likely to report third-party forwarding of sexual content at T2. Bullies are more likely to later report third-party forwarding of sexts. Conclusions: A focus on bullying behavior may be important for intervention efforts targeting to prevent possible negative outcomes of engaging in sexting. Recommendations are provided for educational and prevention efforts.