STD (Subscriber Trunk Dialing) codes are an essential part of India’s national telephone numbering system. These numeric prefixes are used to make long-distance and intercity landline calls across the country. Each STD code is assigned to a specific city, district, or geographic region, allowing telephone networks to route calls accurately and efficiently.
Whether you are trying to identify the origin of a landline call or need the correct dialing prefix to connect with another city, understanding how STD codes work can help ensure seamless communication within India.
STD codes are geographic identifiers used in India’s fixed-line telephone network. When a caller places a long-distance call, the STD prefix tells the telecom system which region or city the call should be directed to. This system was introduced to simplify dialing and eliminate the need for operator-assisted trunk calls.
Major metropolitan cities typically have shorter STD codes due to high call volumes, while smaller towns and rural areas are assigned longer prefixes. For example, Mumbai uses the code 022, whereas smaller towns may use five-digit prefixes.
STD codes are primarily associated with landline services. Mobile numbers follow a separate numbering format and do not rely on geographic area codes in the same way.
Making an intercity landline call within India is simple and follows a standard dialing format:
For example, to call a landline number in Bengaluru from another city, dial 0, followed by 080, and then the local phone number.
International calls from India require the prefix 00, followed by the country code and the relevant area or city code of the destination.
Below is a reference list of commonly searched Indian cities along with their associated telephone dialing regions:
To find the correct STD code for any city, district, or state in India, online directories provide quick and reliable access to updated information. These platforms allow users to search by location name and instantly retrieve the relevant dialing prefix.
Findandtrace.com offers a comprehensive STD code directory covering all Indian states and cities. Users can browse codes by region or search directly using a city or district name to get accurate and up-to-date results.
Fixed-line telephone services in India are offered by the following major telecom providers:
Despite the widespread use of mobile phones, STD codes remain a vital part of India’s telecommunications infrastructure. They support landline connectivity, business communications, government services, and call routing across the country’s vast and diverse regions.
Understanding how these dialing prefixes work helps users make accurate long-distance calls, identify call origins, and navigate India’s telephone system with confidence.
The STD code is a prefix used to dial fixed line or landline numbers across different locations in India. It is also known as an area code or phone code. Unlike many other countries, India maintains a clear distinction between fixed line numbers and mobile numbers across all states and union territories. Before making a call, you must include the appropriate area code along with a zero for fixed line calls.
STD (Subscriber Trunk Dialing) codes in India are assigned to different states, regions, and cities to facilitate efficient long-distance and intercity communication. The distribution is organized to manage the vast telephone network across the country.
STD codes in India range from 2 to 5 digits, with the length generally reflecting the size of the area served. For example, a longer code may be used for a densely po]ulated city, while a shorter code might be assigned to smaller areas. All STD codes begin with a '0' when dialed from outside the area.
Major cities like Mumbai, Delhi, Kolkata, and Chennai each have unique STD codes—022 for Mumbai and 011 for Delhi. States and union territories have been allocated a range of STD codes based on their geographical size and population density. For instance, Tamil Nadu has codes such as 044 for Chennai, while smaller states may have shorter codes.
The allocation of STD codes is based on several criteria including population and demand. Larger cities and heavily populated areas are assigned more extensive code ranges to accommodate higher phone line volumes. Additionally, geographical size and administrative divisions influence the distribution of codes.
The Department of Telecommunications (DoT), under the Ministry of Communications, manages the allocation and oversight of STD codes in India. The DoT periodically reviews and adjusts codes to address changes in population, administrative boundaries, and technological advancements.