Diet Coke Price at Costa Coffee (2026)
A Diet Coke costs £3.25 at Costa Coffee in United Kingdom (updated September 2026).
Wondering how much a Diet Coke costs at Costa Coffee in the United Kingdom? The current price is £3.25. That's about 2% above the average Costa Coffee Chilled Drink item — the 7th-most-expensive of 17 we track. It's available at around 40 Costa Coffee locations across the United Kingdom. Prices are sourced from delivery platforms and refreshed regularly. Compare it against other brands or set a free price-drop alert on MenuPriceToday.
How this compares in Chilled Drinks
17 items tracked| This item | £3.25 |
| Chilled Drinks median | £3.25 |
| Cheapest — Innocent Kids Smoothie | £2.25 |
| Most expensive — Innocent Plus Citrus Shield Juice | £4.20 |
| vs Chilled Drinks median | 0% |
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