Abstract Background Carotid web (CaW) and carotid free-floating thrombus (CFFT) are rare yet critical causes of ischemic stroke in young adults. Case presentation A 54-year-old woman presented with a fluctuating right sensory-motor faciobrachial syndrome. A brain MRI scan revealed multiple small recent asynchronous cortico-subcortical ischemic foci in the vascular territory of the left internal carotid artery. A CT angiography identified a CFFT in the left internal carotid artery arising from an underlying CaW. The patient was treated with excellent clinical outcomes with carotid artery stenting and dual antiplatelet therapy. Conclusions We provide a structured pathophysiological rationale connecting CaW and CFFT and highlight pivotal therapeutic implications. Further studies are needed to investigate this relationship and guide assessment and treatment.