India Phone Numbers: Format, Area Code & Validation Guide

Understanding Phone Numbers in India

Quick Reference

  • Country: India
  • Country Code: +91
  • International Prefix: 00
  • National Prefix: 0

Overview

India's telephone numbering plan is a critical component for telecom professionals, developers, and system administrators. This comprehensive guide covers the Indian phone number structure, formats, and dialing procedures, including country codes, area codes, number lengths, and specific dialing rules for both domestic and international calls. Additionally, it delves into the regulatory framework, number allocation strategies, and recent advancements affecting the Indian numbering plan.

Table of Contents

  1. History of India's Numbering Plan
  2. Regulatory Framework
  3. Indian Number Formats
  4. Dialing Procedures
  5. Number Portability
  6. Major Telecom Operators and Number Ranges
  7. Number Allocation and Management
  8. Technical Considerations for Indian Phone Numbers
  9. Future Developments in India's Numbering Plan
  10. Recent Changes to the Numbering Plan
  11. References

History of India's Numbering Plan

India's telephone numbering system has evolved significantly since the assignment of the country code "+91" by the International Telecommunication Union (ITU) in the 1960s. The initial National Numbering Plan was established in 1993, a time when telecommunications services were predominantly provided by government entities with limited competition. Recognizing the need for scalability and flexibility, the Department of Telecommunications (DoT) introduced the revised National Numbering Plan (NNP) in 2003 to accommodate the burgeoning demand for both fixed and mobile services.

Regulatory Framework

Department of Telecommunications (DoT)

The Department of Telecommunications (DoT) under the Ministry of Communications is the primary regulatory body responsible for the allocation and management of phone numbers in India. The DoT oversees the implementation of numbering plans, ensuring compliance with national and international standards.

Telecom Regulatory Authority of India (TRAI)

The Telecom Regulatory Authority of India (TRAI) plays a pivotal role in shaping telecommunications policies, including recommendations for numbering resource management. TRAI's research and consultation processes influence updates to the National Numbering Plan, ensuring it remains aligned with technological advancements and market dynamics.

Indian Number Formats

General Number Structure

India adheres to the E.164 international numbering plan established by the International Telecommunication Union (ITU). The standard format consists of 10 digits for most phone numbers, structured as follows:

  • Country Code: +91
  • Area/City Code: 2-4 digits (varies by region)
  • Subscriber Number: 6-8 digits (depending on the length of the area code)

Number Format Table

TypeFormat ExampleRegex Pattern
Landline+91 XX XXXX XXXX^\+91[2-9]\d{1,3}\d{6,8}$
Mobile+91 XXXXX XXXXX^\+91[6-9]\d{9}$
Toll-Free000800 XXXXXXX^000800\d{7}$
Premium Rate186X XXXXXXXXX^186[12]\d{9}$
Shared Cost1860 XXXXXXX^1860\d{7}$
Short Code5-digit (e.g., 58888)^5\d{4}$
Telemarketing140 XXXXXXX^140\d{7}$

Detailed Number Formats

Landline Numbers

Landline numbers in India consist of an area code followed by a subscriber number. The area code ranges from 2 to 4 digits, while the subscriber number spans 6 to 8 digits.

  • Format: +91 XXX XXXX XXXX
  • Example: +91 22 1234 5678 (Mumbai)

Mobile Numbers

Mobile numbers are uniformly 10 digits long, starting with digits 6, 7, 8, or 9. Due to Mobile Number Portability (MNP), the initial digits no longer strictly indicate the service provider.

  • Format: +91 XXXXX XXXXX
  • Example: +91 98765 43210

Toll-Free Numbers

Toll-free numbers begin with "000800" followed by seven digits, allowing callers to reach businesses without incurring call charges.

  • Format: 000800 XXXXXXX
  • Example: 0008001234567

Premium Rate Numbers

Premium rate numbers start with "1861" or "1862" and are followed by nine digits. These numbers typically offer value-added services at higher call rates.

  • Format: 186X XXXXXXXXX
  • Example: 18612123456789

Shared Cost Numbers

Shared cost numbers begin with "1860" followed by seven digits. They split call charges between the caller and the service provider.

  • Format: 1860 XXXXXXX
  • Example: 18601234567

Short Codes

Short codes are typically five digits long, starting with the digit '5'. They are used by businesses for services like SMS marketing, voting, and customer support.

  • Format: 5XXXX
  • Example: 58888

Telemarketing Numbers

Telemarketers use 10-digit numbers starting with "140", allocated by the Department of Telecommunications (DoT) upon TRAI's request.

  • Format: 140XXXXXXX
  • Example: 1401234567

Dialing Procedures

Domestic Calls

  • Within the Same Area Code: Dial the subscriber number directly.
  • To a Different Area Code: Dial 0 followed by the area code and the subscriber number.
    • Example: To call a Mumbai number from Delhi, dial 022 XXXXXXXX.

International Calls

  • Outgoing: Dial 00 followed by the country code, area code, and subscriber number.
    • Example: To call a US number from India, dial 00 1 XXX XXX XXXX.
  • Incoming: Dial +91 followed by the area code (without the leading 0) and the subscriber number.
    • Example: To call an Indian number from the US, dial +91 XX XXXXXXXX.

Number Portability

India has implemented Mobile Number Portability (MNP), allowing users to retain their mobile numbers when switching between operators within the same service area. Available nationwide since 2011, MNP enhances competition among telecom operators by enabling subscribers to change providers without changing their phone numbers. This system simplifies numbering plan administration and encourages efficient use of numbering resources.

Major Telecom Operators and Number Ranges

OperatorNumber Range Prefixes (Example)
Bharat Sanchar Nigam Ltd (BSNL)+91 94XX XXXXX
Vodafone Idea (Vi)+91 98XX XXXXX
Reliance Jio+91 70XX XXXXX
Airtel+91 99XX XXXXX
MTNL+91 99XX XXXXX

Note: These prefixes are indicative and can vary based on the service type and region.

Operator-Specific Prefixes

Fixed-line numbers also incorporate operator-specific prefixes, which are the first digit of the subscriber number:

OperatorPrefix
BSNL / MTNL2
Jio3
Airtel4
MTS / HFCL5
Tata Indicom6
Datacom Solutions7

Example: A fixed-line number formatted as (020) 3xxx-xxxx represents a number in Pune operated by Jio.

Number Allocation and Management

Allocation Mechanism

The Department of Telecommunications (DoT) manages the allocation of number blocks to service providers based on usage and demand. The process involves:

  1. Request Submission: Service providers must demonstrate utilization thresholds (60% for mobile, 80% for fixed-line) before requesting additional number blocks.
  2. Evaluation: DoT assesses the current usage and future demand projections.
  3. Allocation: Numbers are allocated in blocks, with sub-levels available to optimize resource utilization.

Pricing of Numbers

Currently, service providers receive number allocations free of charge. However, international practices suggest implementing fees to encourage efficient use of numbering resources. Potential pricing models include:

  • One-time Charge: A fixed fee per number or block.
  • Annual Charge: Recurring fees based on allocated or active numbers.

Proposed Fees:

  • Mobile Numbers: ₹5.00 per number
  • Fixed Numbers: ₹1.00 per number

These charges aim to deter hoarding and promote optimal allocation, ensuring that numbering resources remain sustainable.

Technical Considerations for Indian Phone Numbers

Regular Expressions for Validation

Developers handling Indian phone numbers can utilize the following regular expressions for validation:

  • Landline: ^\+91[2-9]\d{1,3}\d{6,8}$
  • Mobile: ^\+91[6-9]\d{9}$
  • Toll-Free: ^000800\d{7}$
  • Premium Rate: ^186[12]\d{9}$
  • Shared Cost: ^1860\d{7}$
  • Short Code: ^5\d{4}$
  • Telemarketing: ^140\d{7}$

Special Cases

  • Golden Numbers: Numbers with repeating digits (e.g., 99999) are marketed at premium rates.
  • Number Blocking: To mitigate spam and fraud, certain numbers may be blocked by operators.
  • Number Portability Implications: MNP affects the purity of number allocations, necessitating flexible management strategies.

Future Developments in India's Numbering Plan

Next Generation Networks (NGN)

Next Generation Networks (NGN) represent the future of telecommunications in India, integrating fixed and mobile networks to deliver high-speed data, voice, and video services over a unified IP-based infrastructure. Key aspects include:

  • Convergence: Seamless integration of PSTN, mobile, and internet services.
  • Scalability: Enhanced capacity to handle increasing data traffic.
  • Flexibility: Support for innovative services and applications.

Impact of Number Portability

The introduction of Mobile Number Portability (MNP) has streamlined numbering administration by allowing the transfer of numbers between operators without altering their original allocation. Future implications include:

  • Efficient Resource Utilization: Reduced need for new number allocations.
  • Enhanced Competition: Operators must focus on service quality to retain subscribers.
  • Administrative Simplification: Easier management of numbering resources amidst operator changes.

Recent Changes to the Numbering Plan

While the core structure of India's numbering plan remains aligned with the E.164 standard, recent updates focus on:

  • Implementation of MNP: Enhancing flexibility and competition among mobile operators.
  • Introduction of Short Codes: Expanding services like SMS marketing and customer support.
  • Allocation Adjustments: Releasing underutilized number blocks and optimizing resource distribution.

For the most up-to-date information on telecommunications regulations in India, please consult the official websites of the Department of Telecommunications (DoT) and Telecom Regulatory Authority of India (TRAI).

References

  1. Telecommunications Regulatory Authority of India (TRAI) Reports
  2. Department of Telecommunications (DoT) Official Website
  3. International Telecommunication Union (ITU) E.164 Recommendation
  4. National Numbering Plan 2003
  5. Telecom Regulatory Authority of India – Number Portability

For the most up-to-date information on telecommunications regulations in India, please consult the official websites of the Department of Telecommunications (DoT) and the Telecom Regulatory Authority of India (TRAI).

Appendix

Annexure-1: NNP 2003 and Relevant License Conditions

National Long Distance License

  • Network Standards: Adherence to the National Fundamental Plan and technical standards prescribed by DoT.

Basic Service License / International Long Distance License

  • Network Standards: Compliance with the National Fundamental Plan and technical standards by DoT and TRAI.

Cellular Mobile Telephone Service

  • Number Plan: As per ITU-T recommendations, conforming to the National Numbering Plan.

Unified Access Service

  • Numbering Plan: Linked to the Short Distance Charging Area (SDCA) based numbering scheme.

Annexure-2: Number Portability Statistics

Service ProviderIMSI (Sep)HLR (Sep)Difference%age
Bharti114,058,81977,479,21536,579,60432.07%
RTL11,869,0139,206,1272,662,88622.44%
RCL51,495,02046,839,7584,655,2629.04%
Vodafone68,279,19854,624,80913,654,38920.00%
BSNL GSM49,005,95839,166,9439,839,01520.08%
Idea46,654,83230,380,16316,274,66934.88%
Tata29,709,45929,333,049376,4101.27%
Aircel16,337,02113,878,2432,458,77815.05%
Spice5,176,8163,599,7441,577,07230.46%
MTNL GSM3,735,3263,677,88257,5441.54%
MTNL Mumbai WLL(M)72,98561,76411,22115.37%
BPL1,814,8711,663,904150,9678.32%
HFCL WLL(M)417,772302,157-0.00%
Shyam WLL(M)46,32046,32000.00%
Total398,673,410310,259,97888,413,43222.18%
Total884,134,32115,61500.00%

Data continued for October and November 2008.

Annexure-3: Abbreviations Used

AbbreviationMeaning
3GThird Generation Network
CMSPCellular Mobile Service Provider
DNSDomain Name System
ENUMElectronic NUMbering
GPRSGeneral Packet Radio Service
HLRHome Location Register
IMSIInternational Mobile Subscriber Identifier
INIntelligent Network
IPInternet Protocol
LDCALong Distance Charging Area
MNPMobile Number Portability
MSCMobile Switching Center
NGNNext Generation Network
NGN-eCONext Generation Network Expert Committee
NNPNational Numbering Plan
NSNNational Significant Number
PoIPoint of Interconnect
PSTNPublic Switched Telephone Network
SCPService Control Point
SDCAShort Distance Charging Area
SIPSession Initiation Protocol
UASLUnified Access Service License
URIUniform Resource Identifier
USSDUnstructured Supplementary Service Data
VoIPVoice over Internet Protocol
WiFiWireless Fidelity
WiMAXWorldwide Interoperability for Microwave Access