| Dragon Cleaning Services | Carpet cleaning service | 2 Forest cottages, Castle Rd | Mon–Fri 08:00–20:00 |
| Drift-In Launderette & Dry Cleaners | Laundry service | 104 Salisbury Rd | Mon–Tue 09:00–18:00 |
| Drum Depot | Drum shop | The Old Warehouse Next to The Pumping Station & Elephant Beds, Penarth Rd | Mon–Fri 10:00–17:30 |
| Dyffryn Springs Wedding Venue | Wedding venue | Home Farm | Mon–Thu 12:00–23:00 |
| Eastern Business Park | Business park | Wern Fawr Ln | Fri 09:00–15:00 |
| Echa Microbiology Ltd | Aerospace company | Unit 22 and 23, Willowbrook Technology Park, Llandogo Rd | Mon–Fri 09:00–17:00 |
| Eden Landscapes and Garden Buildings | Garden building supplier | Pugh's Garden Village Wenvoe, Port Rd | Thu 09:00–16:30 |
| Elevens Bar And Grill | Sports bar | 15 Castle St | Mon 17:00–23:00 |
| Elliot & Hill Estate Agents | Property consultant | 137 Arabella St | Mon–Fri 08:30–18:30 |
| Ely & Caerau Hub | Library | Cowbridge Rd W | Mon–Wed 09:00–18:00 |
| Embark Studio | Internet marketing service | 12 Ardwyn | Mon 09:00–17:00 |
| Emboss Outdoors | Carport and pergola builder | Pughs Garden Centre, Port Rd | Tue 09:00–17:30 |
| En Pointe Theatre Arts | Dance school | Primary School, Heol Pontprennau | Sat 09:00–21:00 |
| Energie Fitness Cardiff St Mellons | Gym | Building One Eastern Business Park Suite 3-8 | Daily Open 24 hours |
| Energy Saving Grants | Energy equipment and solutions | Sophia House, 28 Cathedral Rd | Mon–Fri 09:00–17:00 |
| Energy Solutions (Es) Ltd | Energy advisory service | Unit : 20 Neptune Ct, Vanguard Way | Mon–Fri 09:00–18:00 |
| Enlightened Movie Posters | Cinema equipment supplier | 24 Brynteg | Daily Open 24 hours |
| Entertainment in Wales | Event planning service | Sophia House, 28 Cathedral Rd | Mon 09:00–17:00 |
| Euro Quality Coatings Ltd | Powder coating service | Wentloog Corporate Park | Mon–Sat 09:00–17:00 |
| Evans and Jones Solicitors, LLP | Lawyer | 8B Station Rd | Mon–Thu 09:00–17:30 |
| Explore Campers | Campervan and caravan rental agency | 4th Floor, EXPLORE CAMPERS LTD, 14 Museum Pl | Mon–Fri 09:00–17:00 |
| Express Imaging Ltd | Photography shop | 172-174 City Rd | Mon–Sat 10:00–18:00 |
| Feet In Focus Podiatry & Chiropody | Chiropodist | 32 Churchill Way | Tue–Wed 08:45–17:30 |
| Fforest Oak Flooring | Flooring contractor | Unit 14 | Thu 09:00–17:00 |
| Financial Planning Business Ltd | Financial planner | First Floor Office, 5 Station Rd | Mon–Fri 09:00–17:00 |
| Fine Tune Piano | Piano tuning and repair service | 313 Railway St | Mon–Fri 08:30–19:00 |
| Fino Lounge | Eclectic restaurant | 49 Merthyr Rd | Mon 08:30–23:00 |
| Firestorm Games Cardiff | Toy shop | Sloper Rd | Mon 10:00–18:00 |
| Firing Line Cardiff Castle Museum of the Welsh Soldier | Tourist attraction | Castle St | Mon–Fri 10:00–16:00 |
| First Encounters Ultrasound Cardiff | Medical diagnostic imaging centre | Gate Business Park, Unit 1, Ground Floor Brook House Lime Tree Court, Mulberry Dr | Mon–Fri 08:00–20:30 |