A 350 ml americano from Starbucks has 89 mg of caffeine, a little under one mug of instant coffee. The same size at Costa has 325 mg, more than three mugs. We went through the published figures for the five biggest UK high street chains to find how much caffeine is in coffee, drink by drink, and why the number in your cup is so hard to guess.
Contents
- The short version
- The numbers, chain by chain
- Why the same drink varies so much
- Cup size is a poor guide
- What it does to your daily total
- How to cut down without giving up the habit
The short version
Costa is the strongest of the big five and Starbucks the weakest. A medium Costa americano or cappuccino is 325 mg, over three mugs of instant coffee, and a large one is 400 mg, which is the whole of the daily amount EFSA considers safe for a healthy adult. A Starbucks Tall, much the same size, is 89 mg. The caffeine follows the number of espresso shots, so a bigger cup does not always mean more. Two medium coffees from the stronger chains can put you past 400 mg before lunch.
The numbers, chain by chain
These are the chains' own figures. Costa and Starbucks publish caffeine in their UK nutrition guides. Caffè Nero, Greggs and Pret publish none that we could find, so theirs come from a Which? comparison of each chain's stated caffeine content, published on 25 August 2026 (Which?, 2026).
A regular or medium drink
| Chain | Americano | Cappuccino | Latte | Flat white | Single espresso |
|---|---|---|---|---|---|
| Costa | 325 mg | 325 mg | 200 mg | 241 mg | 100 mg |
| Greggs | 257 mg | 235 mg | 150 mg | 150 mg | 75 mg |
| Caffè Nero | 191 mg | 221 mg | 105 mg | 105 mg | 67 mg |
| Pret | 180 mg | 180 mg | 180 mg | 180 mg | 180 mg |
| Starbucks (Tall) | 89 mg | 89 mg | 89 mg | 89 mg | 45 mg |
Costa figures are for a medium, from Costa's autumn 2026 caffeine table (Costa, 2026). Starbucks figures are for a Tall, the 12 oz cup, from its summer 2026 UK guide (Starbucks UK, 2026). A Grande americano, the next size up, is 134 mg. The rest come from Which?. Which? lists a Costa latte at 241 mg, while Costa's own table gives 200 mg for a medium, so the table uses Costa's figure. Cup sizes differ between chains, so read the table as the order you would actually place at each counter.
Filter and cold brew
- Pret filter coffee: 271 mg
- Starbucks filter coffee: 210 mg
- Starbucks cold brew: 193 mg Tall, 265 mg Grande, 285 mg Venti
Costa, Nero and Greggs don't sell filter coffee. Where it is on the menu it tends to be the strongest thing there, and the Starbucks cold brew carries three times the caffeine of the latte in the same size.
A large Costa americano or cappuccino is four shots and 400 mg. That one cup reaches the most EFSA considers safe for a healthy adult across a whole day.
Matcha lattes
Which? also tested hot matcha lattes. Costa's has 99 mg (340 ml), Starbucks' matcha green tea latte has 57 mg (354 ml) and Pret's has 28 mg (355 ml). Costa's is about a mug of instant. The Starbucks one has more caffeine than a Starbucks espresso shot, which is 45 mg. Matcha is lower than a coffee of the same size at the same chain, and it still has caffeine, so count it if you are cutting down.
Why the same drink varies so much
An americano is espresso and hot water. What changes between chains is how much espresso goes in, and how strong each shot is.
- Costa builds a medium americano on three shots and a large on four. A Starbucks Tall has two.
- The shots differ too. A Costa espresso is 100 mg and a Starbucks one is 45 mg. Pret pours its single espresso at 50 ml and 180 mg, about twice the volume of a Starbucks shot.
- Costa's flat white uses three short "cortissimo" shots, 241 mg in total. Three full shots would be 325 mg.
- Robusta beans carry roughly twice the caffeine of arabica, and each chain uses its own blend.
The published figure is an average
Even at one chain, the cup in your hand can sit well above or below the menu figure. A 2012 study in Food & Function tested 20 espressos bought on the high street and found a sixfold range. The strongest single espresso held 322 mg, and three more were over 200 mg (Crozier et al., 2012). The authors put most of the difference down to how much ground coffee the barista used.
A larger follow-up tested 104 espressos from coffee shops in Scotland, Italy and Spain. The range was 48 to 317 mg per serving, and the researchers concluded that "one cup of coffee" is not a reliable unit of measurement (Ludwig et al., 2014).
The figures in the table are what the chains aim for. The cup you are handed on a busy morning can land a long way either side.
Cup size is a poor guide
Most people assume a large has more caffeine than a small. Often it doesn't, because milk drinks get bigger by adding milk, and the shots stay the same.
- A Starbucks Grande latte has the same 89 mg as a Tall. You pay for the extra milk.
- A small Costa latte is one shot and 100 mg if you drink it in. Take it away and it becomes two shots and 200 mg, because the takeaway cup is bigger than the in-store one.
- At Costa, a small cappuccino (200 mg) has twice the caffeine of a small latte drunk in.
To know what is in your cup, ask how many shots it has.
What it does to your daily total
The European Food Safety Authority says a healthy adult can take up to 400 mg a day, and up to 200 mg in one go, without safety concerns (EFSA, 2015). Pregnancy is lower, and we covered why in our post on caffeine in pregnancy.
Run an ordinary working day through those numbers:
- A medium Costa cappuccino on the way in: 325 mg
- A Pret filter coffee mid-morning: 271 mg
That is close to 600 mg by 11am, or about six mugs of instant. Each of the two drinks is over the 200 mg single-dose guide on its own. At Starbucks, a Tall cappuccino and a filter coffee come to about 300 mg. In pregnancy the limit is 200 mg for the whole day, so one medium Costa cappuccino is over it (the 200 mg pregnancy limit).
Timing matters as much as the total. Caffeine has a half-life of about 6 hours, so every drink stacks on top of the ones before it, and a late coffee leaves more in your system at bedtime than an early one. We walked through that in how long caffeine stays in your system.
Our caffeine calculator adds up your drinks and shows how much is still in you when you go to bed. Put in your real chain and cup size, because the same drink name can mean 89 mg or 325 mg.
If you have been counting energy drinks and ignoring coffee, the energy drinks vs coffee comparison shows how the two stack up.
How to cut down without giving up the habit
You can take a lot of caffeine out of your day without changing where you go.
- Ask for one shot fewer. At Costa that takes a medium americano from 325 mg to 200 mg.
- Go down a size at Costa, where the size decides the shot count. At Starbucks, a Tall latte already has the same caffeine as a Grande.
- Order your second coffee as decaf. A Costa decaf is 2 mg.
- Skip filter coffee and cold brew in the afternoon.
Cutting down suddenly can bring on headaches and brain fog for a few days, particularly if you are used to 400 mg or more. Clinical guidance recommends cutting by roughly a quarter every few days, which is what our caffeine reset guide covers.
If you would rather follow a plan
The Uncaffed 30-day reset kit runs that taper on a fixed schedule:
- Reset steps your caffeine down from 160 mg a day to 120, 80, 40 and then none, five days at each step, with L-theanine alongside.
- Flow has no added caffeine and runs for all 30 days.
- For the 30 days, the capsules are your only caffeine. Decaf, herbal tea and rooibos keep the ritual going.
Preorders are open. Kits ship by 30 October. The quiz helps you work out your starting point, and the science page explains how the steps were chosen.
