If the Calling Boost is the UK Anytime Unlimited UK Calls Boost then it includes all standard UK landlines starting 01, 02 and 03 and mobiles* all day, every day for no extra charge.
You can talk for up to 60 minutes free on each call before being charged at the standard rate. But if you'd like to talk for longer than 60 minutes, just hang up and redial and it's free again.
*Calls to the Channel Islands, Isle of Man, dial-up internet, indirect access and all other numbers are not included. Please see our pricing page for a full list of charges.
*Note, voicemail charges are separate and are not included with any other calling boosts.