In addition to the MNOs in the UK there are a number of Mobile Virtual Network Operators. These organisations sell mobile network services to customers but do not run their own network. They will purchase space on the network of a MVO and resell to their customers. The product they sell will be rebranded and the customer will not be aware that the organisation only resells and does not run a mobile network.

The coverage ofa MNVO wil be identical to that of their host MNO. So for example Tesco Mobile coverage is the same as that of O2. There is still no internal roaming within the UK. If this were to be allowed a MNVO would be able to switch their customers from one network to another dependent on the coverage at a location. Assuming that the commercial contracts were in place. This would put the MNVO at an advantage over the MNO, so whilst technically an excellent service, commercially this is fraught with difficulty.

Amongst the Mobile Virtual Network Operators in the UK are :

• Virgin Mobile that run on the EE network.
• Tesco Mobile that run on the O2 network.
• Asda Mobile that run on the EE network.
• Sainsbury Mobile that run on the Vodafone network.
• TalkTalk mobile that run on the Vodafone network, soon to change to O2.
• BT Mobile that run on the EE network.
• Sky Mobile that run on the O2 network.

In addition three of the mobile operators run their own virtual network. The reasons are varied, but essentially to market to a different customer base. For example Vodafone has a reputation as a "business" network but their VOXI network is marketed to a young audience.

The operator owned mobile virtual networks are :

• GiffGaff wich is iwned by O2 but run by the GiffGaff community
• Smarty which is run by THREE
• VOXI whih is run by Vodafone