| Roynon Performing Arts | Performing arts group | New Rd | Daily 09:00–22:00 |
| Sage Mind Clinical Hypnotherapy | Hypnotherapy service | 37 Coleridge Dr | Mon–Fri 10:00–19:00 |
| Saint Patrick's Catholic Church | Catholic church | 45 Portsmouth Rd | Mon–Fri 09:00–13:00 |
| SALADMASTER BestLife Health Investment Limited | Cooking class | 6, Freemantle Business Centre, 152 Millbrook Rd E | Daily 09:00–17:00 |
| Samuel's Rest | Pub | Upper Church Rd | Mon–Sat 12:00–23:00 |
| Sea Sky Design | Art gallery | The Old Post Office, High St | Tue–Fri 10:30–16:30 |
| SeaCity Museum | Tourist attraction | Havelock Rd | Mon–Sat 10:00–16:30 |
| Seashells Bar & Restaurant | Modern British restaurant | 37 High St | Mon–Thu 10:00–22:00 |
| Shaftesbury House Sheltered Accommodation - Sanctuary Housing Association | Sheltered housing | 113a Paynes Rd | Daily Open 24 hours |
| Shanghai 1814 Restaurant | Shanghainese restaurant | 165 High St | Mon–Thu 12:00–14:30, 17:00–23:00 |
| Shanghai Garden | Chinese restaurant | 4, Forest Hills Dr | Mon–Tue 17:00–23:00 |
| Simple Design Services Partnership | Structural engineer | 183A Botley Rd | Mon–Fri 07:00–18:00 |
| Slice & Bites Southampton | Pizza takeaway | 1A Bedford Pl | Mon–Thu 12:00–00:00 |
| So Make It | Makerspace | Unit F, liners industrial estate | Daily 08:00–22:00 |
| Southampton (Formally EST1897). | Pawn shop | Unit 19, Marlands shopping centre, Civic Centre Rd | Mon–Sat 09:30–17:30 |
| Southampton Chauffeur Hire | Tour operator | 464 Winchester Rd | Daily 08:00–20:00 |
| Southampton City Judo and Sumo Club | Judo school | Parity Martial Arts and Wellness, Millbank St | Wed 18:00–19:30 |
| Southampton Common | Park and garden | The Avenue | Daily Open 24 hours |
| Southampton General Hospital | General hospital | Tremona Rd | Daily Open 24 hours |
| Southampton Household Waste Recycling Centre | Recycling centre | City Depot & Recycling Park, First Avenue | Daily 09:00–12:30, 13:00–18:00 |
| Southampton Logs | Firewood supplier | 188 N E Rd | Mon Open 24 hours |
| Southampton PDSA Pet Hospital | Animal hospital | 40-46 Mount Pleasant Rd | Mon–Fri 09:00–18:00 |
| Sprinkles Gelato Above Bar | Dessert restaurant | 120-122 Above Bar St | Daily 10:00–00:00 |
| Sprinkles Gelato Portswood | Ice cream shop | 160 Portswood Rd | Daily 10:00–00:00 |
| St Denys Boat Club | Club de voile | Priory Ave | Daily 06:00–23:00 |
| St James Road Methodist Church | Methodist church | St James Road Methodist, St James Rd | Mon–Sat 08:00–22:00 |
| St James' Church | Anglican church | Church Hill | Tue–Fri 09:00–15:00 |
| Stephanie's Celebrations | Balloon artist | Botany Bay Rd | Daily Open 24 hours |
| Steven Swann Antiques | Antique furniture shop | 185 N E Rd | Daily 08:00–20:00 |
| Sunnyfields Farm Shop | Farm shop | Sunnyfields Farm, Jacob's Gutter Ln | Mon–Fri 09:00–18:00 |