(1) Background: Submandibular gland (SMG) sialolithiasis treatment has shifted significantly, favouring minimal invasiveness. Nonetheless, transoral stone removal remains viable for distal, deep hilar, and intraparenchymal stones. However, data are limited regarding recurrence and revision surgery; (2) Patients/Methods: This retrospective study included 226 patients with SMG stones treated using Wharton's duct slitting and marsupialisation over nine years; 138 had deep hilar or intraparenchymal stones, while 88 had distal stones. Of the former group, 18 experienced symptom recurrence post-surgery, 12 with stones and 6 with duct stenosis; (3) Results: Of the 126 patients without recurrent stones, 71% were male and 29% were female. Their mean age was 51.02 ± 9.36 years. The stones of the 126 patients without recurrence had a diameter of 8.3 mm ± SD: 4 mm, which was significantly smaller than those of the patients who experienced recurrence (13.8 mm ± SD: 2.4 mm; p < 0.05). The mean estimated stone growth recurrence rate was 8.4 ± SD: 1.8 mm per year. A secondary operation was performed 34 ± SD: 14.7 months after the first. Of the patients with recurrence, 91.7% were treated under general anaesthesia. The preferred treatment for 58.4% of patients was intraoral revision operation; the remainder underwent total gland resection. The mean follow-up period was 43 ± SD: 18 months; (4) Conclusions: The rate of revision surgery was relatively low. In recurrent SMG sialolithiasis, new stones may grow faster than the primary stones, which are already larger than those in patients without recurrence. The slitting and marsupialisation of Wharton's duct can treat recurrent cases.