The Indonesian government mandated that prepaid mobile phone users register their SIM cards using their National Identity Number (NIK) from their KTP (National Identity Card) and Family Card by February 28, 2018. A single NIK can register a maximum of three cards. Failure to register will result in sanctions, including blocking of incoming calls, text messages, outgoing calls, and data services.
Based on data from six mobile operators, the number of mobile phone cards (prepaid and postpaid) in circulation reached 392.78 million units. Of this number, Telkomsel leads with 178 million units, or approximately 45.3% of the total. This is followed by Indosat Ooredoo with 96.4 million units (24.54%) and Tri with 56.8 million units (14.46%). With 392.78 million mobile phone cards and a population of approximately 262 million, the ratio of mobile phone users to the population is almost 150%. This means that each person uses more than one mobile phone card.
(Read Databoks: [Miliki 119 Ribu BTS, Telkomsel Menjadi Operator dengan Jangkauan Terluas](http://databoks.katadata.co.id/datapublish/2016/09/01/miliki-119-bts-telkomsel-menjadi-operator-dengan-jangkauan-terluas))
The large number of mobile phone cards in circulation is partly due to people using more than one card, particularly for calls and data, using different cards for each. Additionally, many cards are not properly registered because they are intended for single use to take advantage of initial data package promotions.