Mobile number portability allows mobile subscribers to switch operators while keeping their phone number. There are three types of number portability: operator, location, and service portability. India launched MNP in 2009, allowing subscribers to change operators after 90 days for a fee of up to 19 rupees. MNP benefits both customers and service providers by increasing competition and forcing providers to improve services. However, customers can only change operators within their registered circle and are restricted from changing too frequently.