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Ritha (Sapindus mukorossi) is an economically and ecologically valuable multipurpose tree species which is widely distributed across the tropical and subtropical regions of South and Southeast Asia. This species is gaining commercial significance due to its multi-utility for natural detergents, pharmaceuticals, cosmetics, biofuel, Ayurveda and traditional medicine. Despite its wide-range uses, large-scale plantations of Ritha are constrained by poor and inconsistent seed germination which is caused primarily by a hard and impermeable seed coat that induces physical dormancy. The present study was conducted to investigate fruit and seed morphology as well as to evaluate the efficacy of different pre-sowing treatments on seed germination and early seedling growth under greenhouse conditions during 2024-2025 at Tree Propagation Nursery, College of Horticulture and Forestry, Neri, Hamirpur, Himachal Pradesh. Six pre-sowing treatments viz., untreated seeds (control), concentrated H₂SO₄ (20 min), GA₃ (1000 ppm), PEG (10%), hot water (80 °C for 2 h) and cold water (48 h) were employed. Fruit length ranging from 24.40–27.62 mm, seed length from 13.24–16.22 mm and seed weight from 1.48–1.98 g was observed in Ritha seed morphology. Germination response varied significantly among treatments and the highest germination percentage (87.50%) was observed in concentrated H₂SO₄ seed treatment which representing a 21% increase over the control. Seedling growth parameters viz., seedling height, collar diameter, root length and leaf area were also maximized under H₂SO₄ treatment followed by hot water treatment. Acid scarification proved most effective in breaking hard-seeded dormancy in Ritha by enhancing water permeability which improving germination kinetics and seedling vigour. Standardizing pre-sowing treatments can substantially improve nursery propagation and promote wider adoption of Ritha in agroforestry and plantation programmes in the subtropical region of Himachal Pradesh.