Introduction: Persistent hyperparathyroidism is usually due to a missed parathyroid adenoma, which can be located at variable though well-described locations within the neck and mediastinum due to the gland's embryological descent. We describe a rare case of an intravagal parathyroid adenoma that illustrates the benefit of multiple localisation modalities. Case summary: A 43-year-old man was referred with primary hyperparathyroidism. Sestamibi demonstrated uptake of equivocal suspicion posterior to the right hemithyroid; ultrasound of this area was negative. Initial exploration failed to find an adenoma or left inferior parathyroid. Repeat sestamibi, 4D-CT and selective venous sampling localised the adenoma to the left upper neck. An intravagal parathyroid adenoma was identified intraoperatively with gamma probe and completely excised. The patient was biochemically cured and had normal vocal cord function at follow up. Discussion: Awareness of the possibility of intravagal parathyroid adenoma is important, especially in cases where preoperative localisation is uncertain. Intraoperative localisation with gamma probe can be a useful adjunct to achieve cure in such cases. Keywords: Parathyroid adenoma, Hyperparathyroidism, Ectopic, Gamma probe