The company has added the 5p charge to all beverages served in a plastic cup, and customers who bring a reusable cup in-store will be eligible for the existing 25p discount.
During the three-month trial across 35 London outlets, Starbucks worked with environmental charity Hubbub in order to compile a report on the success of the trial. The report showed the number of customers bringing in their own cup or tumbler increased in trial stores from 2.2% before the trial to 5.8% during the trial.
It was also found that mornings were the most popular time for customers to bring in a cup, with 8% of customers going reusable. Money raised by the 5p charge is to be donated to supporting recycling and sustainability work at Hubbub.
Starbucks also recently announced plans to eliminate the use of plastic straws globally by 2020, creating a new strawless lid for iced coffee, tea and espresso beverages.
Martin Brok, president of Starbucks Europe, said: “We saw encouraging results from the first three months of this trial with Hubbub, and what stood out to us was the positive response we had from our partners and customers who continue to push us to innovate and find ways to reduce waste.
“Extending this to all our stores across Britain is an exciting step and we’re hoping this charge will remind customers to rethink their use of single-use plastic as it has with plastic bags.”
Trewin Restorick, CEO and founder of Hubbub said: “Single-use plastics is an issue that has become more significant in people’s minds than ever before. The trial proved this, showing that customers have an increased awareness of the need to reduce waste from single-use cups.
“A 5p charge is an effective way to prompt this change. We’re excited to be working with Starbucks, particularly as they take on board the findings of the trial and introduce the charge across the whole of the UK. We look forward to discovering what more can be done to encourage people to use reusable cups.”