Virgin Mobile, still majority owned by Sir Richard Branson, piggybacks the T-Mobile mobile network. Offering contracts is aimed at poaching customers from T-Mobile, Vodafone, O2 and Orange, as well as at migrating its own pre-pay customer base.
Around two-thirds of non-company mobile phone users are on prepay, but the one-third who are on contracts are far more lucrative, accounting for around two-thirds of the industry's revenues.
Shares in Virgin Mobile slipped 1p today to 203p, extending their recent falls from a high of 280p earlier this year.