Starbucks is testing a 5p paper cup charge across its London stores to reduce the amount of waste it creates.
The scheme, which automatically adds the fee to the cost of a coffee, will be trialled across 35 London locations to see whether customers will actually stop using single-use paper cups in favour of greener alternatives.
Starbucks-commissioned research found almost half of the public said they would carry a reusable cup to save money and cut waste.
It has offered a £1 reusable cup since 2014 to allow customers to do this easily.
The company says the proceeds from the charge will be donated to environmental charity and behaviour change expert Hubbub, which will help to track the impact of the initiative.