A system that allows people to pay in a cheque by taking a photo on their smartphone is being made available to a million more customers.
From Monday, customers of Barclays' Premier Account will be able to photograph their cheques and send them electronically.
The pilot project has the backing of the government.
Barclays says up to £300m worth of UK cheques a year are never paid in, compared with £840bn deposited.
Customers still have the option of paying in paper cheques at bank branches, cash machines, post offices and by post.
The new technology, launched earlier this year to a few thousand people, is currently only available to customers using an iPhone.
Barclays said that it planned to extend the pilot to Android-based smartphones next year, as well as to business customers.
The system is similar to imaging projects already established in the US, France and parts of Asia.
It also marks a further move towards self-service, instead of counter-based banking.