Source-backed comparison
Costa vs Starbucks latte caffeine in the UK
Compare the published UK caffeine figures for a Costa Medium Signature Blend Latte and Starbucks Grande Caffè Latte with source provenance.
| Measure | Costa Signature Blend Latte | Starbucks UK Caffè Latte |
|---|---|---|
| Named serving | Medium | Grande |
| Market | UK | UK |
| Caffeine per serving | 200 mg | 89.1 mg |
| Caffeine per 100 ml | Not available from source | Not available from source |
| Value basis | Calculated from manufacturer table | Manufacturer listed |
| Estimated after 5 hours | 100 mg | 44.5 mg |
How to interpret the comparison
- Costa’s Medium Latte estimate is 200 mg, derived by combining its published two-shot recipe with its published two-shot caffeine value.
- Starbucks UK directly lists 89.1 mg for its standard Grande Caffè Latte.
- The named sizes are not asserted to have equal volumes. This is a standard-menu serving comparison, not a concentration comparison.
Calculated five-hour timeline
This table applies the same exponential half-life equation to both starting amounts. It does not show measured blood levels or predict which drink will affect a particular person more.
| Hours after serving | Costa Signature Blend Latte | Starbucks UK Caffè Latte |
|---|---|---|
| 0 | 200 mg | 89.1 mg |
| 3 | 132.0 mg | 58.8 mg |
| 5 | 100 mg | 44.5 mg |
| 8 | 66.0 mg | 29.4 mg |
| 10 | 50 mg | 22.3 mg |
| 12 | 37.9 mg | 16.9 mg |
Sources
- Costa Coffee UK store guideGuide applies 30 April–26 August 2026.
- Starbucks UK Nutrition & Allergen GuideGuide version 16 April 2026; standard recipe before customisation.