The club feels the shirt sponsorship market has greatly increased in recent years, while Vodafone is said to want to build on its sponsorship of Manchester United in new areas.
Both parties are keen to continue their relationship and are exploring an ongoing sponsorship deal.
Premier League champions Chelsea signed a five-year deal with electronics firm Samsung, before the start of the new season, worth a reported £50million (or £10million a year). This eclipsed United's four-year deal with Vodafone, said to be worth £9million a year.
Manchester United have said there are no plans for a naming rights deal relating to its Old Trafford stadium.
Vodafone also announced yesterday (Wednesday) an exclusive three-year deal to sponsor the UEFA Champions League from July next year.
It sees the mobile telecomms company become both an Official Partner and the Official Mobile Network of the Champions League.
As well as branding and hosting rights - and a substantial broadcast sponsorship package - it will also deliver content including video highlights packages and goal alerts from all Champions League matches to football fans on the Vodafone live! with 3G consumer service.
