Introduction: In recent decades, the endovascular treatment of cerebral arteriovenous malformations (AVMs) has advanced. However, it still carries risks of unanticipated complications. Coil migration is a reported complication of aneurysmal coiling procedures. Herein, we report a case of early intraprocedural coil migration during pressure cooker technique embolization of right thalamic AVM, discussing the management and potential explanations. The literature showed no report of coil migration after the pressure cooker technique in the form of coil-augmented Onyx injection technique (CAIT). Case description: An otherwise healthy 26-year-old female suddenly developed a severe headache with no loss of consciousness. Computed tomography (CT) scan of the head illustrated intraventricular haemorrhage. Magnetic resonance imaging (MRI) showed the bag of worms' sign in the right thalamic area. The size and location of the AVM prompted the decision for multistage endovascular embolization using onyx. In the anterior circulation, the right A5 arterial feeder has a high flow which indicates the pressure cooker technique embolization in the form of CAIT. In the procedure, early detachment and migration of the coil occurred in the medial prefrontal branch through the anterior cerebral artery. No intervention to retrieve the coil was carried out because the detachment piece is small and lodged distally. Onyx was injected directly without the coil because of the risk of radiation to the patient. Otherwise, the intraprocedural and postprocedural courses went uneventful. Conclusion: This is the first report of coil migration during the pressure cooker technique with CAIT for the right thalamic AVM.