Complete third branchial arch anomalies are rare and have been described only in case reports, affecting mainly children and typically presenting as a cervical inflammatory process. Anomalies of the third and fourth branchial apparatus, though rare, usually present as sinuses/incomplete fistulas of pyriform sinus or recurrent suppurative thyroiditis. A 6-year-old girl presented with a small opening on the left side of her anterior neck, which had been present since birth and was associated with recurrent infection. She had no history of incision and drainage of swelling. Computed tomography with contrast injection into the cervical opening revealed a fistulous tract extending from the cervical neck skin to the pyriform fossa. Complete excision of the fistulous tract and left hemithyroidectomy were performed. There was no recurrence at 22 months of follow-up.