Yes, 4Freedom Mobile provides coverage across the UK.
In the UK, 4Freedom Mobile uses the networks of Vodaphone, O2, and 3, so Volta Wireless should be able to provide the largest possible coverage area.
Please note that all 4Freedom Mobile Private Numbers are US or Canadian phone numbers, and 4Freedom Mobile does not currently support the porting in of non-US/Canada phone numbers. We do plan to launch a pilot program for international number porting later this year. Please let us know if you would like to participate in that pilot program.
Even though 4Freedom Mobile numbers are all US/Canadian, you will still have unlimited calling to any number in the UK or anywhere else in the world.