Hypereosinophilic syndrome (HES) is a rare haematologic disorder characterised by unexplained, persistent eosinophilia with organ involvement. We report the case of a 74-year-old patient who presented with a pemphigoid-like bullous rash as the only manifestation of an HES. This report highlights the importance of the dermatological manifestations of this potentially life-threating condition that may initially present as a skin-limited disease. Bullous pemphigoid (BP) is a very common autoimmune blistering dermatosis that may share common clinical and histological features or associate with an HES. HES should be considered when patients diagnosed with BP demonstrate atypical course under corticosteroids and/or recalcitrant blood eosinophilia.