The number of subscribers who successfully ported their mobile number has used 100 million mark, telecom regulator Telecom Regulatory Authority of India (TRAI) said in a statement.

Mobile number portability (MNP) is a facility for the mobile telephone user which allows them to retain their mobile telephone number when they moves from one access provider to another access provider in the same service area irrespective of the mobile technology or from one cellular mobile technology to another of the same access provider.

MNP was introduced across the country in January 2011. Introduction of MNP has empowered the mobile subscriber and given them freedom to change their service provider without changing their mobile number.

Keeping in view the consumer interests, TRAI prescribed a porting charge of Rs 19 which is among the lowest in the world.

In 2011, the porting request rejection rate was around 40 percent which has been brought down to 11 per cent now. In this process, TRAI issued a number of directions and orders to the telecom service providers.

In addition, financial disincentives to the tune of about Rs 8 crore have also been levied on various service providers, wherever they have been found in violation of MNP regulations on account of wrongful rejection of porting requests, it said.