Arriva UK Bus is a major bus operator in the United Kingdom based in Sunderland, England. It is a subsidiary of Arriva which runs transport services across Europe, which has been a subsidiary of Deutsche Bahn since 2010.

Arriva UK Bus operates 5,900 buses in London, the North East, North West and South East of England, Yorkshire, The Midlands and Wales. It employs 16,000 people.