0844 [581/811/848 etc] – For BT residential customers, calls will cost no more than 5.5p per minute, plus 13.1p call set-up fee (current at December 2012). The price on non-BT phone lines may be different. Please check the BT price list for charges for other 0844 numbers as charges vary depending on the three digits following 0844.
Calls to 0800, 0808 and 0500 numbers are free if made from a UK landline. Non – BT customers and mobile phone users should contact their service providers for information about the cost of calls.