| D J Evans Forse & Co Funeral Directors | Funeral director | Whitchurch Funeral Home, Whitchurch Common | Daily Open 24 hours |
| Dalchini | Breakfast | Indian Restaurant | Breakfast restaurant | 10 MacKintosh Pl | Mon 09:30–14:00, 17:00–23:00 |
| DAX Studio | Web designer | Unit 4, Boomerang Parc | Mon–Sat 08:00–18:00 |
| DD Glass Balustrades (Cardiff) | Railing contractor | Sophia House, 28 Cathedral Rd | Daily Open 24 hours |
| Deccan Express | Variety shop | 123 Richards St | Mon–Thu 10:00–18:00 |
| Deja Vu Wales | Second-hand clothing shop | 1, 200 Pontcanna St, Kings Rd | Sat–Sun 10:00–16:00 |
| 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 |
| Dyffryn Springs Wedding Venue | Wedding venue | Home Farm | Mon–Thu 12:00–23:00 |
| Elevens Bar And Grill | Sports bar | 15 Castle St | Mon 17:00–23:00 |
| Energie Fitness Cardiff St Mellons | Gym | Building One Eastern Business Park Suite 3-8 | Daily Open 24 hours |
| Enlightened Movie Posters | Cinema equipment supplier | 24 Brynteg | Daily Open 24 hours |
| 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 |
| Fluidity Freerun Academy | Parkour spot | Freerun Academy, Fluidity, Unit G St Catherines Pk, Pengam Rd | Mon–Fri 11:00–21:00 |
| FRF Toyota Cardiff | Toyota dealer | Hadfield Rd | Mon–Fri 08:30–18:00 |
| Fussy Vintage | Vintage clothing shop | 1A Mortimer Rd | Wed–Sat 11:00–17:00 |
| G R C Plumbing & Heating Ltd | Central heating service | Castle Court, Cae'r Graig | Daily Open 24 hours |
| G.M Music | Musical instrument shop | 2 Wharton St | Mon–Sat 09:30–17:30 |
| Glenwood Church & Wellbeing Space | Church | Cir Way W | Mon–Thu 09:30–15:30 |
| Global Drone Surveys | Aerial photographer | 3rd Floor, Capital Tower, Business Centre | Daily 08:00–20:00 |
| Golf Fang Cardiff | Cocktail bar | Mary Ann St | Mon–Thu 15:00–22:00 |
| Grange Gardens | City park | 126 Holmesdale St | Daily Open 24 hours |
| GSG Plumbing and Heating | Gas engineer | 37 Dorchester Ave | Daily Open 24 hours |
| Hangar Human Performance Centre | Gym | Penarth Rd | Mon–Fri 06:00–21:00 |
| Havana Shisha Lounge | Shisha bar | 152-154, City Rd | Daily 14:00–02:00 |
| Havens Foods Cardiff | African goods shop | 103-104 Clifton St | Mon–Fri 08:00–22:00 |
| Heath Hotel | Pub | Whitchurch Rd | Mon–Thu 12:00–23:00 |