Caffeine Levels in UK Coffee Shops: Costa, Starbucks, Greggs and Pret Compared

A new Which? study reveals major differences in caffeine levels across UK coffee chains, with some cappuccinos containing far more caffeine than others.

New research reveals surprising caffeine differences between popular coffee chains

For many people in the UK, grabbing a coffee on the way to work is part of the daily routine. However, a new study suggests that the amount of caffeine in a seemingly similar drink can vary dramatically depending on where it is bought.

Research from consumer organisation Which? has highlighted significant differences in caffeine levels across drinks sold by major UK high street coffee chains, including Costa Coffee, Starbucks, Greggs, Caffè Nero and Pret A Manger.

The findings suggest that customers ordering the same type of drink from different retailers could consume substantially different amounts of caffeine without necessarily realising it.

The research is particularly relevant for people who drink several caffeinated beverages each day or have been advised to limit their caffeine intake.

Costa cappuccino contains the highest caffeine level

One of the most striking findings concerns cappuccinos.

According to the Which? research reported by The Independent, a medium cappuccino from Costa contained 325mg of caffeine.

That figure was significantly higher than the caffeine content found in comparable cappuccinos at other chains. A cappuccino from Greggs contained 235mg, while Caffè Nero's version contained 221mg.

Starbucks recorded the lowest level among the chains tested, with a medium cappuccino containing 89mg.

This means the Costa cappuccino contained more than three times the caffeine found in the Starbucks equivalent.

The difference is substantial enough to challenge the assumption that a standard cappuccino will contain roughly the same amount of caffeine regardless of where it is purchased.

How much caffeine is in other popular coffee drinks?

The differences were not limited to cappuccinos.

Costa was also found to have the highest caffeine content for several other drinks. Its single espresso contained 100mg of caffeine, while its flat white contained 241mg.

Starbucks, by comparison, recorded 45mg for its espresso and 89mg for its flat white in the research.

These figures demonstrate why consumers who are monitoring their caffeine intake may need to look beyond the name of a drink.

A flat white, cappuccino or espresso can have very different caffeine levels depending on the coffee chain, recipe, serving size and number of shots used.

For regular coffee drinkers, those differences can quickly add up over the course of a day.

Caffeine levels have changed at some chains

The Which? research also compared some of its latest findings with earlier testing carried out in 2023.

Costa's caffeine levels for cappuccinos and single-shot espressos were reported to be broadly unchanged since the previous study.

Caffè Nero, however, showed a notable increase. The caffeine content of its cappuccino was around twice the level recorded in the earlier research.

Starbucks also saw increases in caffeine levels in some drinks, including espresso, cappuccino and filter coffee.

This highlights another important issue for consumers. Caffeine levels are not necessarily fixed over time, meaning people who regularly order the same drink may want to check the latest nutritional information rather than relying on older figures or assumptions.

Matcha drinks can contain more caffeine than expected

Coffee is not the only source of caffeine attracting attention.

Matcha has become increasingly popular in the UK, with coffee shops adding hot and iced matcha drinks to their menus. Although matcha is often viewed as an alternative to coffee, it still naturally contains caffeine.

The study found considerable differences between chains.

Costa's hot matcha latte contained 99mg of caffeine, compared with 57mg at Starbucks and 28mg at Pret A Manger.

For someone trying to reduce caffeine consumption, switching from coffee to matcha does not automatically mean choosing a caffeine-free option.

The amount consumed can depend on the recipe and quantity of matcha powder used, making it important to check nutritional information when available.

Why caffeine levels matter

For most healthy adults, moderate caffeine consumption can form part of a normal diet. However, sensitivity to caffeine varies from person to person.

Consuming too much caffeine can cause symptoms such as difficulty sleeping, restlessness, nervousness, headaches or a rapid heartbeat in some people.

People who consume several coffees, energy drinks, tea or caffeinated soft drinks during the day may also underestimate their total intake.

Caffeine limits can be particularly important for certain groups, including pregnant people and anyone who has been advised by a healthcare professional to reduce their caffeine consumption.

The latest findings therefore underline the importance of knowing what is actually in a drink rather than judging its caffeine content simply by its size or name.

How consumers can make more informed choices

The easiest way to manage caffeine intake is to check the nutritional information provided by the coffee chain.

Customers can also consider ordering smaller drinks, choosing decaffeinated options or reducing the number of caffeinated drinks consumed throughout the day.

It is also worth remembering that coffee strength does not always correspond to taste. A drink that tastes mild can still contain a considerable amount of caffeine, while a stronger-tasting coffee may contain less depending on how it has been prepared.

For people who regularly visit different coffee chains, checking caffeine information each time may therefore be more useful than assuming that one standard drink has a consistent caffeine level everywhere.

Coffee choice can make a surprisingly big difference

The new research offers a useful reminder that coffee menus can be more complicated than they appear.

Two medium cappuccinos may look almost identical, yet their caffeine contents can differ by hundreds of milligrams. For customers who drink coffee occasionally, this may not be a major concern. For people consuming several caffeinated drinks every day, however, those differences can become significant.

The findings also show that caffeine is not limited to coffee. Popular alternatives such as matcha can contain meaningful amounts as well.

Consumers who need to monitor their caffeine intake should therefore pay attention to the specific product, serving size and nutritional information provided by each retailer.

Source

This article is based on research by Which?, as reported by The Independent on 25 August 2026.

Disclaimer

This article is intended for general informational purposes only and is based on the source material available at the time of writing. Caffeine content can vary according to drink size, recipe, preparation method and product changes. Nutritional information may also be updated by individual retailers. This article is not medical advice. Anyone who has been advised to restrict caffeine, including during pregnancy or because of a medical condition, should follow guidance from an appropriate healthcare professional and check the latest information provided by the retailer.