Contemporary education increasingly involves a blended learning environment, which consists of a combination of offline and online delivery methods. Blended learning environments can motivate students to learn, but designing motivating blended learning environments is challenging and can result in environments that demotivate students. This conceptual article proposes a blended learning design that helps practitioners to design motivating blended learning environments. According to self-determination theory, students are motivated to learn when their three basic psychological needs for autonomy, competence, and relatedness are supported. Competency-based education (CBE) is intended to support students’ basic psychological needs. We have constructed design guidance for CBE programmes that help practitioners to design a combination of offline and online delivery methods that (1) give students choices in time and place to support their need for autonomy, (2) adapt to students’ competency levels to support their need for competence, and (3) stimulate students’ relationship building with peers and teachers to support their need for relatedness. Although the design guidance is tentative, practitioners can experiment with it to design blended learning environments that motivate students to learn.