Costa Coffee Flat White contains 241 mg of caffeine per Medium 299 ml (299 ml / 10.1 oz). That is about 2.5 times the caffeine of a typical 8 oz cup of brewed coffee (about 95 mg). Concentration: 80.6 mg per 100 ml.
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Costa Coffee Flat White Caffeine Content by Serving
Figures are for Flat White (Costa Coffee).
| Serving | Volume | Caffeine | Per 100 ml | Level |
|---|---|---|---|---|
| Medium 299 ml | 299 ml / 10.1 oz | 241 mg | 80.6 mg | High |
Source: caffeine figures from Caffeine Informer (values from Costa Coffee nutrition info and customer service), accessed 2026-06-11. Values can vary by batch, location, and preparation; check the label or the source for the latest figures.
How Costa Coffee Flat White Compares to Coffee
At 241 mg per Medium 299 ml, Costa Coffee Flat White delivers about 2.5 times the caffeine of a typical 8 oz cup of brewed coffee (about 95 mg). For a wider comparison across drinks, try the caffeine comparison tool or browse the full caffeine database.
When to Stop Drinking Costa Coffee Flat White Before Bed
With caffeine's median 5-hour half-life, a Medium 299 ml of Costa Coffee Flat White (241 mg) needs about 11 h 21 min to fall under 50 mg, the level where most people can fall asleep normally. That puts the last call at 10:30 AM (10:30) for a 10 PM bedtime and 11:30 AM (11:30) for an 11 PM bedtime. Individual half-lives range from roughly 2 to 12 hours, so treat these as a starting point.
The Costa Coffee Flat White sleep cutoff page has last-call times for four bedtimes, and the caffeine half-life calculator personalizes the curve to your metabolism.
