To identify the mobile numbers that which mobile number is of which service provider and of which area , for that there is plan which is called telephone numbering plan which describe the information about any mobile number in India. All mobile number in India start with 9, 8, 7 or 6 which are based on GSM, WCDMA and LTE technologies. In 10 Digits Indian mobile number statring four digit identifies the telecom circle and last six digits identifies the subscriber. A telephone numbering plan is a type of numbering scheme used in telecommunication to assign telephone numbers to subscriber telephones or other telephony endpoints. Telephone numbers are the addresses of participants in a telephone network, reachable by a system of destination code routing. Telephone numbers in India are administered under the National Numbering Plan of 2003 by the Department of Telecommunications of the Government of India. The numbering plan was last updated in 2015. The country code "91" was assigned to India by the International Telecommunication Union in the 1960s.

Here is the list of various sim operators operating in India.

For a variety of purposes, India's telephony regulators have divided the country up into a number of regions, called 'Telecom Circles' or 'Telecom Service Areas'. You will see reference to these telecom circles in various situations. For example: when looking for telephone numbers or telephone directories you will generally need to search by telecom circle. Or when reviewing telephone service plans and coverage areas for the telephone companies, you will see these may vary by telecom circle. Also, if a telephone company wants to operate in a specific telecom circle, they must purchase a license for that circle, usually through an auction process.