For the first time in over four months since mobile number portability (MNP) kicked in across the country, Vodafone Essar has slipped to the number two position on the list of operators who gained the most number of customers, as of May 30.

According to the latest data, from the MNP clearing house, Idea Cellular has overtaken Vodafone, albeit marginally, to gain the top spot. Idea clocked net gains of 6,39,060, while Vodafone registered gains of 6,33,589 customers since the time MNP was rolled out in January this year.