From 18 January 2010, 6 mobile phone network companies will no longer charge their customers for calls to Department of Work and Pension's 0800 Benefit Claim Lines for Jobseeker's Allowance, State Pension, Pension Credit, and the Employment and Support Allowance.

The mobile phone network companies are O2, Orange, Tesco Mobile, T-Mobile, Virgin Mobile and Vodafone.

You can read Department of Work and Pension's press release here http://www.dwp.gov.uk/newsroom/press-releases/2010/january-2010/dwp007-150110.shtml