Telephone numbers in India Telephone numbers in India Telephone numbers in India are administered under the "National Numbering Plan of 2003" by the Department of Telecommunications. The numbering plan was last updated in 2015. The International Telecommunication Union has assigned the country calling code "91" to India. Subscriber Trunk Dialling (STD) codes are assigned to each city/town/village, with the larger Metro cities having shorter area codes (STD codes), which are from 2 to 8 digits long. For example, Tier-2 Cities or culturally significant towns in India have STD code with 3 digits. For example, Kanpur and Lucknow were the two cities between which the
Subscriber trunk dialling when the Queen, who was in Bristol, publicized it by dialling Edinburgh – the farthest distance a call could be directly dialled. The STD system was completed in 1979, though most of the country was covered well before then. The system required that a new STD code, which could be dialled by subscribers, be allocated to each area; in the UK area codes are still sometimes called STD codes. With the introduction of subscriber trunk dialling each city with a Director system was assigned a 3-digit code, in which the second digit corresponded to the first letter of the city