Background Normocalcaemic primary hyperparathyroidism (NPHPT) is often under‐recognised in clinical practice. Aim To determine the prevalence and clinical significance of NPHPT in an unselected sample in an acute hospital setting. Methods Patients aged >18 years who had measurement of an elevated serum parathyroid hormone (PTH ≥ 7 pmol/L) during 12 months from 1 January 2017 to 31 December 2017 were retrospectively studied. NPHPT was defined by the presence of elevated serum PTH with normal albumin‐corrected serum calcium on two or more occasions after excluding secondary causes. Patients were followed up for 2 years. Relevant data were collected by review of electronic medical records. Results Of the 2593 patients who had PTH measured during the study period, 1278 had serum PTH ≥ 7 pmol/L. Hypercalcaemic primary hyperparathyroidism (PHPT) was diagnosed in 174 patients. Secondary causes for elevated serum PTH were identified in 993 patients: 815 (chronic kidney disease – estimated glomerular filtration rate < 60 mL/min/1.73 m2 or renal transplant), 98 (vitamin D deficiency – 25(OH)D < 50 nmol/L), 28 (gastric bypass surgery), 38 (medications), 13 (malabsorption or post‐thyroidectomy) and 1 (hypercalciuria). Data were incomplete for 80 patients. The prevalence of NPHPT with and without the exclusion of hypercalciuria was 0.19% (5) and 0.39% (10) respectively. The prevalence of nephrolithiasis in NPHPT was higher than PHPT (100% vs 15% among five patients (P < 0.001) and 50% vs 15% among 10 patients (P = 0.014)). The prevalence of osteoporosis was not significantly different between NPHPT and PHPT (20% vs 45% among five patients (P = 0.389) and 30% vs 45% among 10 patients (P = 0.518)). Conclusion These findings give further credence to the diagnosis of NPHPT as a clinical entity. Nephrolithiasis may be a greater problem than osteoporosis in NPHPT compared with PHPT. This needs prospective evaluation.