Yes! Many great charities, political organisations, and nonprofits in the United Kingdom are using Donorbox.
Donorbox also has the ability for your UK donors to mark donations as Gift Aid.
Your can turn on the Gift Aid earmark in your Donorbox account settings. https://donorbox.org/org/edit
This will display a UK designation check box during the donation checkout process.
In the UK, Stripe charges a low rate of 1.4%+ 20p for European cards. See Stripe's pricing detail at https://stripe.com/gb/pricing
Stripe may also offer a discounted nonprofit rate for registered nonprofits. Please email email@example.com for details