Introduction: In everyday clinical neurophysiology practice, mononeuropathies are evaluated primarily by traditional electrodiagnostic testing. We sought to assess the additional benefit of neuromuscular ultrasound (US) in this scenario. Methods: All consecutive mononeuropathies undergoing combined US and electrodiagnostic evaluation over a 23‐mo period at a single neurophysiology practice were reviewed. Three independent examiners assessed how often US was: (a) "contributory" ‐ enabling a definite diagnosis not made by electrophysiology alone and/or impacting on the therapeutic decision, (b) "confirmatory" of the electrodiagnostic findings, but not adding further diagnostic or therapeutic information, or (c) "negative" ‐ missed the diagnosis. Results: There were 385 studies included. US was "contributory" in 36%, "confirmatory" in 61% and "negative" in 3%. Discussion: In this study of everyday neurophysiology practice, neuromuscular US contributed significant diagnostic or therapeutic information in over 1/3 of the investigations for common mononeuropathies. False negative US studies were uncommon in this setting. See Editorial on pages 437–438 in this issue. [ABSTRACT FROM AUTHOR]