With the rise of global transnational terrorist networks (GTTNs), there has been an increase in scholarly output on the subject. While many scholars have focused on the ways in which these networks enable terrorist organizations to achieve their goals, few have studied the transformative impact that GTTNs have on group cohesion. In order to fill this gap, I seek to answer the question how, if at all, GTTNs affect the likelihood of armed groups experiencing fragmentation. In doing so, I propose three ways in which GTTNs can influence cohesion among their members and explore these in the cases of al-Shabaab and Boko Haram, while using the Taliban as a counterfactual. Although I find that both GTTN members and non-members experience fragmentation, the ways in which fragmentation manifests itself differs. Whereas the Taliban experienced fragmentation following key events, al-Shabaab and Boko Haram experienced splits as a result of long-term processes. Thus, GTTN membership ostensibly reinforces internal processes that may cause factions to split from the organization, thereby increasing the risk of fragmentation. However, more research is required on the different ways through which GTTNs exert influence over their members and the effect this has on the risk of fragmentation.