| Arctic Ice | Ice supplier | Ashmead Business Centre, North Cres | Mon 09:00–20:00 |
| Are They Safe Private Investigators | Private investigator | 1st Floor, 2 Woodberry Grove | Daily Open 24 hours |
| Arepa & Co Venezuelan Restaurant - Haggerston | Venezuelan restaurant | 58A De Beauvoir Cres | Mon–Thu 12:00–22:00 |
| Argile Paints | Paint shop | 555 King's Rd | Mon–Fri 09:30–18:00 |
| Aria One Six Eight | Furniture store | 168 Upper St | Mon–Sat 10:00–18:30 |
| Aristocracy London | Tienda de esmóquines | 15 Cromwell Rd | Mon–Tue 10:00–18:00 |
| Arla Brasserie | Brasserie | 475-477 High Rd. Leyton | Mon–Fri 08:00–21:00 |
| Arnos Grove Post Office | Post office | 468 Bowes Rd | Mon–Fri 08:00–18:00 |
| ARO Multi Services | Carpet cleaning service | 78A Park Hall Rd | Mon–Fri 08:00–18:00 |
| Aroma Buffet W12 | Shepherds Bush | Buffet restaurant | West 12 Shopping Centre, Unit B,1st floor, West12 Shopping Centre | Mon 12:00–15:00, 17:00–22:00 |
| Aroma Tandoori Indian Takeaway | North Indian restaurant | Unit 5-6, Greyhound Ln | Daily 11:30–22:00 |
| Art Dental Academy | Dental school | 29 Weymouth St | Mon–Fri 08:00–16:00 |
| Art4Space | Art centre | 31 Jeffreys Rd | Mon 10:00–18:00 |
| Artem Restoration | Blast cleaning service | 5, Leigham Hall Parade, Streatham High Rd | Mon 08:00–18:00 |
| Articulate Music | Band | 40 Fernwood Ave | Daily Open 24 hours |
| Artisa Spa | Massage spa | 359 High Rd. Leyton | Mon–Sat 10:00–22:00 |
| Artisan Furniture | Tienda de muebles | 2A Monck St | Mon–Fri 09:00–17:00 |
| Artisan Implants & Caring Dentistry | Dentist | 192 Westcombe Hill | Mon–Tue 09:00–17:00 |
| Artisans of Sardinia Ltd | Southern Italian restaurant | 16 Lacy Rd | Tue–Sat 12:00–14:30, 18:00–22:30 |
| Artisans.Life | Artistic handicrafts | 230 Morning Ln | Mon–Wed 10:00–18:30 |
| ArtNHer London | Handicraft | Studio 69, 2nd floor, Arebyte Studios, 25-27 Camden Rd | Tue–Sat 11:30–16:30 |
| Arts Students' Union | Student union | 272 High Holborn | Mon–Fri 10:00–16:00 |
| ASAP Distribution - Film & TV Consumables | Office supplies shop | Unit 14 Sovereign Park, Coronation Rd | Mon–Fri 08:00–17:00 |
| Ascot Rehab Hospital | Physical rehabilitation center | 6 Aldrington Rd | Mon–Fri 08:00–18:00 |
| ASG Community Gymnastics Club | Gymnastics academy | Arch 11 Byron Cl | Daily 08:00–21:00 |
| Ashbourne Healthcare Services | Home health care service | Ashbourne House, 35 Harwood Rd | Daily Open 24 hours |
| Ashiana Networks | Domestic abuse treatment centre | 750-760 High Rd Leytonstone | Mon–Fri 09:30–17:00 |
| Asian Dukan | Indian grocery shop | 187-189 Upper Tooting Rd | Mon–Fri 09:00–18:00 |
| Asif Chaudry, Oesophageal Cancer Surgeon, Gastric Cancer Surgeon | Surgical oncologist | The Royal Marsden, 203 Fulham Rd. | Daily Open 24 hours |
| Astons Law | Criminal defence lawyer | First Floor, 85 Great Portland St | Daily Open 24 hours |