River Radio is now covering Berkshire, South Buckinghamshire, South Oxfordshire and North Hampshire on DAB following its online launch last year.
The service was created 12 months ago by directors Sam Sethi and Michael Bourton.
“Mike and I saw a great opportunity to serve a region of seven million people with hyper-local community shows highlighting businesses and people from the Thames Valley,” said Sam Sethi, Managing Director, River Radio.
Michael Bourton, Commercial Director added: “We believe that the future success of River Radio will be down to the talented presenters we can attract both now and in the future.
“They should benefit from our station’s growth, which is why we have made them all co-owners in the radio station.”
River Radio is now live on the Berks & North Hants multiplex.