In the early age of telephone systems it was only possible to connect inside one exchange (Local Call) only. During subscribe want to connect a specific number he/she first need to dial the telephone exchange operator. Then manually operator need to connect an another subscriber on the same exchange. Later with the growing technology it was possible to connect another exchange. In real-time you don’t feel it is very difficult to handle multiple requests by operator manually. That’s the cause telephone exchange department decided to introduce specific codes for specific exchange. Rather a name or string Codes are more effective in digitization.
The same story happened & every exchange has its own specific code. Let’s take an example if you want to dial a number in Bhubaneswar (553261) from Mumbai, then first you need to dial 0674 to connect Bhubaneswar exchange then you can dial the specific number 553261 to connect the receiver. Today no one is manually operating to connect you from one exchange to other exchange. Computer is taking care of all by just looking the code. This code is called “Subscribers Trunk Dialing”. In short hand it is popular as STD Codes. In the below table we are presenting all important cities of India & their respective STD Codes. For your reference you can take a print out or can use CTRL + F option to search.
How STD Codes Work
An STD code is typically a 2- to 4-digit number prefixed before the local telephone number.
For example:
Mumbai: 022
Delhi: 011
Bangalore: 080
When making a long-distance call, the caller must dial:
1. International Access Code (if calling from abroad).
2. Country Code (e.g., +91 for India).
3. STD Code (without the leading ‘0’).
4. Local Phone Number.
Example: To call a number in Delhi from abroad, dial +91 11 XXXX XXXX.
Understanding JIO Fiber
Jio Fiber, launched by Reliance Jio, is a high-speed broadband service offering internet, digital television, and voice calling services over a fiber-optic network. Unlike traditional landline services, Jio Fiber provides Voice over Internet Protocol (VoIP) for calls, which operates differently from conventional PSTN (Public Switched Telephone Network) lines.
Does JIO Fiber have an STD Code?
Since Jio Fiber primarily uses VoIP technology, it does not rely on traditional STD codes for long-distance calls. Instead, calls made through Jio Fiber are routed via the internet, eliminating the need for geographic-specific codes. However, Jio Fiber provides landline numbers to its users, which may appear similar to traditional numbers but function differently.
STD Codes
| City | STD Code | City | STD Code |
| Agartala | 381 | Agra | 562 |
| Ahmedabad | 79 | Ajmer | 145 |
| Akola | 724 | Alagappa Nagar | 487 |
| Aligarh | 571 | Allahabad | 532 |
| Alleppy | 477 | Alwar | 144 |
| Ambala | 171 | Amraothi | 721 |
| Amritsar | 183 | Aroor | 478 |
| Assansol | 341 | Attingal | 472 |
| Badagra | 496 | Bajpe | 824 |
| Baliapattom | 497 | Balipatna | 674 |
| Bangalore | 80 | Bareilly | 581 |
| Baroda | 265 | Belgaum | 831 |
| Bethampur | 680 | Bhagalpur | 641 |
| Bhatinda | 164 | Bhavnagar | 278 |
| Bhilai Durg | 788 | Bhopal | 755 |
| Bhuvaneswar | 674 | Bikanir | 151 |
| Bullabhghar | 11 | Bundi | 747 |
| Burdwan | 342 | Burhanpur (MP) | 735 |
| Calicut Khozikode | 495 | Cannanore | 497 |
| Chennai | 44 | Cherpur | 487 |
| Cheruvathur | 499 | Chinnalpatty | 451 |
| Choudwar | 671 | Cochin | 484 |
| Coimbatore | 422 | Crangannore | 488 |
| Cuttuck | 671 | Darjeeling | 354 |
| Derhadun | 135 | Dehuroad | 212 |
| Delhi | 11 | Dhanbad | 326 |
| Dhurva (Ranchi) | 651 | Dibrugarh | 373 |
| Dindigal | 451 | Dispur | 361 |
| Dombively | 251 | Durg | 788 |
| Durgapur | 343 | Dwaraka | 289 |
| Ernakulam | 484 | Erode | 424 |
| Etawah | 568 | Faridabad | 129 |
| Gandhi Nagar (Kerala) | 481 | Gauhati | 361 |
| Gaya | 631 | Ghaziabad | 575 |
| Ghaziapur | 548 | Gorakhpur | 551 |
| Guntur | 863 | Gurgaon | 124 |
| Guruvayur | 487 | Gwalior | 751 |
| Hapur | 122 | Hirehalli | 816 |
| Hublidharwar | 836 | Hyderabad | 40 |
| Ibrahimpatnam | 866 | Imphal | 385 |
| Indore | 731 | Jabalpur | 761 |
| Jagatpur | 671 | Jaipur | 141 |
| Jalgaon | 257 | Jammu | 191 |
| Jamnagar | 288 | Jamshedpur | 657 |
| Jhalukbari | 361 | Jharia | 326 |
| Jodhpur | 291 | Jorhat | 376 |
| Jullundhar | 181 | Junagadh | 285 |
| Kakinanda | 884 | Kalmboli | 215 |
| Kalyan | 251 | Kalyani | 33 |
| Kanpur | 512 | Karnal | 184 |
| Kausa | 215 | Kawaf | 261 |
| Kengeri | 80 | Khandwa | 733 |
| Kolencherry | 484 | Kolhapur | 231 |
| Kolkata | 33 | Konaje | 824 |
| Kota | 744 | Kottayam | 481 |
| Krishnapur | 824 | Kurichi | 422 |
| Lakshadweep | 486 | Lalithpur | 520 |
| Lucknow | 522 | Ludhiana | 161 |
| Madukkarai | 422 | Madurai | 452 |
| Manacha Nallur | 431 | Mancheswar | 674 |
| Mangalore | 824 | Manjeri | 493 |
| Mathura | 565 | Meerut | 121 |
| Melur | 488 | Miraz | 233 |
| Mohali | 172 | Moradabad | 591 |
| Mulamthuruthy | 484 | Mulankunnthukavu | 487 |
| Mumbai | 22 | Muvattupuzsha | 485 |
| Muzaffarpur | 621 | Mysore | 821 |
| Nadiad | 268 | Nagpur | 712 |
| Nasik | 253 | Nellore | 861 |
| New Delhi | 11 | Ollur | 487 |
| Ooty | 423 | Palaymkottai | 462 |
| Palghat | 491 | Panambur | 824 |
| Panjim / Goa | 832 | Pathankot | 186 |
| Patiala | 175 | Patna | 612 |
| Perianaickanpalyam | 422 | Pondicherry | 413 |
| Poranki | 866 | Porbandar | 286 |
| Prithvipur | 144 | Punalur | 475 |
| Pune | 20 | Quilon / Kollam | 474 |
| Raibareli | 535 | Raipur | 771 |
| Rajahmundry | 883 | Rajkot | 281 |
| Rajpur | 135 | Ramanthali | 498 |
| Rampur | 595 | Ranchi Dhurva | 651 |
| Rourkela | 661 | Sachin | 261 |
| Saharnpur | 132 | Salem | 427 |
| Samalkot | 884 | Sambalpur | 663 |
| Sangli | 233 | Shilong | 364 |
| Sholapur | 217 | Siliguri | 353 |
| Simla | 177 | Somarasamettai | 431 |
| Sriganga Nagar | 154 | Srinagar | 194 |
| Srirangam | 431 | Surat | 261 |
| Taliparamba | 498 | Tellicherry | 497 |
| Tinsukia / Digboi | 374 | Tirunelveli | 461 |
| Triuparaithurai | 431 | Tirpunithira | 484 |
| Tirur | 494 | Tiruverambur | 431 |
| Trichur | 487 | Trivandrum | 471 |
| Tumkur | 816 | Turbhe | 22 |
| Tuticorin | 461 | Udaipur | 294 |
| Udhampur | 199 | Ujjain | 734 |
| Ullal | 824 | Uppala | 499 |
| Urlikanchan | 212 | Uttarsandi | 268 |
| Valapad | 487 | Varkala / Ayiroor | 472 |
| Varanasi | 542 | Vellore | 416 |
| Vijayawada | 866 | Visakhapatnam | 891 |
| Vizhinjam | 471 | Waluj | 243 |
| Washi | 215 | William Nagar | 365 |
| Zero | 378 | — | — |
Common Misconceptions about STD Codes
STD codes remain a fundamental aspect of telecommunications, yet misconceptions about their purpose and usage persist. Clarifying these misunderstandings ensures smoother communication and better utilization of telephony services. By recognizing that STD codes are dynamic, region-specific, and applicable beyond landlines, users can navigate long-distance dialing with greater confidence and accuracy. Understanding these nuances eliminates confusion and promotes efficient use of telecommunication networks.
1. STD Codes for Mobile Numbers: Not required; mobile numbers are dialed directly.
2. Leading Zero: Used only for domestic calls; omitted in international dialing.
3. Uniform Length: STD codes vary from 2 to 4 digits.
How JIO Fiber’s VoIP Telephony Works
Jio Fiber’s telephony service operates on VoIP, leveraging its high-speed fiber-optic network to deliver crystal-clear voice quality. Unlike traditional landlines, which require separate wiring, Jio’s service runs over the same broadband connection used for internet access. Users can connect a standard telephone to the Jio Fiber router via an analog telephone adapter (ATA), allowing them to make and receive calls as they would on a regular landline.
A key advantage of Jio Fiber’s VoIP service is its retention of STD codes. In India, STD codes are deeply ingrained in communication habits, serving as geographic identifiers (e.g., 011 for Delhi, 022 for Mumbai). By preserving these codes, Jio ensures users can dial numbers in the same format they always have, eliminating the need to adapt to new numbering systems. This backward compatibility is crucial for businesses, emergency services, and individuals who rely on memorized or printed contact details.
Benefits of JIO Fiber’s VoIP Telephony
Voice over Internet Protocol (VoIP) telephony has revolutionized communication by enabling voice calls over broadband internet rather than traditional phone lines. Jio Fiber, a high-speed broadband service by Reliance Jio, integrates VoIP telephony into its offerings, providing users with seamless, cost-effective, and feature-rich calling solutions.
Cost Efficiency – VoIP calls, especially long-distance and international ones, are significantly cheaper than traditional landline or mobile calls. Jio Fiber offers bundled plans with unlimited local and national calling, reducing communication expenses for households and enterprises.
Enhanced Features – Beyond basic voice calls, Jio Fiber’s telephony includes advanced features like call forwarding, voicemail, caller ID, and multi-device support. Users can manage calls via a smartphone app, enabling mobility without sacrificing landline convenience.
Reliability and Scalability – Fiber-optic networks provide superior voice clarity and uptime compared to aging copper lines. Businesses can easily scale their communication systems without additional hardware, making Jio Fiber ideal for growing organizations.
Future-Proof Infrastructure – As India moves toward digitalization, legacy landline systems are becoming obsolete. Jio Fiber’s VoIP service aligns with global trends, ensuring users stay ahead in an increasingly internet-dependent world.
The Technology behind JIO Fiber
Jio Fiber leverages fiber-optic technology, which transmits data as pulses of light through thin glass fibers. This technology ensures significantly higher speeds and lower latency compared to traditional copper-based broadband connections. Fiber-optic networks are capable of supporting bandwidth-intensive applications such as 4K streaming, online gaming, and cloud computing without compromising performance.
One of the key advantages of Jio Fiber is its symmetrical upload and download speeds. Unlike conventional broadband services, where upload speeds are often throttled, Jio Fiber ensures that users can upload large files, participate in video conferences, and stream content with equal efficiency. This makes it an ideal choice for professionals, students, and businesses alike.
Jio Fiber revolutionizes telecommunication by eliminating the need for STD codes through VoIP technology. Users enjoy seamless, cost-effective calling without geographic limitations. As internet-based services expand, traditional dialing methods will continue to evolve, making communication more accessible and efficient for everyone.
Conclusion
STD codes are indispensable for long-distance communication in India, ensuring efficient connectivity across cities. Whether for personal or professional use, understanding these codes simplifies domestic and international calling. Keeping an updated telephone directory with accurate STD codes enhances communication reliability.