Social movement scholars have long considered organizations (social movement organizations [SMOs]) vital to the success of a movement. SMOs organize events, mobilize participants, and recruit new activists into the movement. In the case of youth activism, SMOs can also play a vital role in the political socialization of youth. However, a substantial line of research finds that most SMOs do a poor job of encouraging and facilitating youth engagement in offline, face-to-face contexts. With the growing use of digital media by both social movements and youth, online activism presents another avenue through which SMOs can recruit youth participation. The extent to which SMOs are doing any better at this online than offline is an open and surprisingly new question, however. Using a unique dataset, we explore the extent to which SMOs are encouraging youth participation in social movement activity online. Based on our findings, we argue that engaging with and recruiting youth into SMOs is vital for the future health of these organizations as well as the political socialization of youth, and that SMOs are not doing enough to recruit youth online, mirroring their failure offline.