The formation of stone in the ductal system of the salivary gland is termed sialolithiasis, with the submandibular gland being the most commonly affected. The precise aetiology is unknown but certain factors peculiar to the submandibular gland accounts for its likelihood of developing a calculous disease. Stones are classified based on their dimension, and may be silent or present with symptoms attributable to the size, location and complications. Here, a 50-year-old female who presented with a painless swelling in the left submandibular region that had grown slowly over the previous year, is reported. Following clinical and radiologic evaluation, left submandibular stone disease was preoperatively diagnosed. The patient underwent sialoadenectomy with transient palsy of the marginal mandibular branch of the facial nerve. Histopathology confirmed sialolith (2.7 cm) with severe squamous metaplasia of the duct. This presentation demonstrates some peculiar features attributable to the size, vertical orientation and location of the stone, in addition to the compression of the gland, thick fibrous capsule and significant squamous metaplasia of the duct. These findings require further evaluation for optimal treatment in view of the emerging trends for managing sialolithiasis.