Consumer champion Which? has found that caffeine levels in popular high street coffee drinks vary “wildly” between chains, with a medium cappuccino from Costa containing 325mg—almost three-and-a-half times the 89mg in the same drink at Starbucks.
The research analysed caffeine content in drinks sold by Caffe Nero, Costa Coffee, Greggs, Pret A Manger and Starbucks. Costa's cappuccino contains the equivalent of around four cans of Red Bull, according to Which?.
Highest and lowest caffeine levels
Greggs and Caffe Nero had the second and third-highest cappuccino caffeine levels, at 235mg and 221mg respectively. Costa also topped the list for its espresso shot, with 100mg per serving, and its flat white, at 241mg.
In contrast, Starbucks' espresso shot contains 45mg of caffeine per serving, and its flat white has 89mg. While Costa's caffeine content for cappuccinos and single-shot espressos has not changed since Which?'s last study in 2023, Caffe Nero's has noticeably increased—its cappuccino now contains around double the level of caffeine than before.
Matcha drinks also vary
Matcha drinks also differ significantly between chains. The study found Costa's hot matcha latte had the highest caffeine content at 99mg, followed by Starbucks at 57mg and Pret at 28mg. The drink, made from green tea powder, has boomed in popularity in recent years, prompting chains to add their own versions to menus.
Which? said its research showed customers should “pay attention” to differences in caffeine levels across high street retailers, particularly those advised to restrict intake for health reasons, including pregnancy.
Chain responses
Jessica Carson, Which? health and wellbeing expert, said: “For many of us, there is nothing quite like a strong cup of coffee to start the day, but Which? found even matcha enthusiasts could be consuming more caffeine than intended.
“Our research shows caffeine content varies wildly from chain to chain.
“If you drink multiple cups a day or need to cut back for health reasons, pay attention to where you shop and what you order to avoid any unwanted side-effects.”
A spokeswoman for Costa said: “At Costa Coffee, we’re committed to helping customers make informed choices. That’s why caffeine and nutritional information is available across our menu and online, so customers can choose the drinks that best-suit their individual preferences and needs.
“We also offer decaffeinated coffee and a range of non-caffeinated drinks. Coffee naturally contains caffeine and levels can vary depending on factors such as the blend, recipe and serving size.”
Starbucks has been contacted for comment.
