India: SIP providers and connecting a number to the PBX

This page continues the general guide to connecting a provider's number to the PBX: that guide covers everything that is the same in any country — the two trunk modes, what to ask the carrier, what to enter in the form, networking and the connection test. This page covers what is specific to India: who may issue a number, whose trunk actually reaches a cloud PBX and whose does not, and which documents you will be asked for.

The data was collected on 10 September 2026 from provider documentation, carrier websites and DoT materials; links are in the "Sources" section.

In brief#

• A dedicated PBX is created for Indian locations — India is not on the list of countries where the server is not provisioned. The difficulty lies elsewhere: you still have to reach the trunk.
• All five carriers — Airtel, Jio, Tata Tele, Vi and BSNL — deliver the trunk over their own last mile, with the session border gateway sitting on a private address such as 10.x.x.x inside the carrier's network. There is no route to it from the cloud — this is not a policy ban, it is the physical absence of a path. Their trunk only works with a PBX on the venue's premises.
• There is exactly one realistic route: cloud providers holding a virtual network operator licence (UL-VNO), whose trunk runs over the ordinary internet. First on the list is Exotel: it is the only company in the country that publishes full parameters (pstn.in2.exotel.com, TCP 5070, IP authentication, G.711 codecs) and keeps a ready-made Asterisk example in its documentation.
• If you need the registration mode, use TeleCMI / PIOPIY: their API issues a login, a password and a gateway address of your own account.
• ⚠️ The number is issued to an Indian legal entity. Exotel requires the company PAN, the certificate of incorporation or MSME registration and proof of address; carriers add the customer application form, the corporate identity number and GST. A venue without an Indian registration is left with international aggregators — and that means inbound calls only.
• ⚠️ Outbound calls with an Indian number may only leave through an Indian licensee. Since 22 October 2024 a government system blocks international calls presenting a spoofed Indian number: a call from abroad showing an Indian caller ID is cut off at the border.

Numbers in the country#

• The country code is +91, the international prefix is 00 and the national prefix is 0. A national number is always 10 digits: the area code takes from 2 to 8 digits, and the bigger the city the shorter the code — the "code + number" total never changes.
• Area codes: 11 Delhi and New Delhi, 22 Mumbai, 33 Kolkata, 44 Chennai, 40 Hyderabad, 79 Ahmedabad, 80 Bengaluru, 124 Gurgaon. In the largest cities the local number is 8 digits, in Gurgaon it is 7.
• Mobile numbers are 10 digits starting with 6, 7, 8 or 9, with no geographic binding; portability between carriers works nationwide.
• Special ranges: 1800 is toll-free for the caller, 1860 is a paid shared-cost range (a common mistake: it is not free), 000800 is the international toll-free range for inbound calls from abroad, and 140XX is the mandatory range for telemarketing.
• In Lines enter the number exactly as the provider issued it. The formats differ: Exotel sends the international form with a plus (+91XXXXXXXXXX), while Tata on its own link sends the national number without the country code. The PBX matches a line by the last seven digits, and for a ten-digit Indian number those seven digits are unique within one account — so any notation works.
• Emergency calls use 112 (the single number); 100, 101, 102 and 108 still work. You cannot rely on them through a trunk into a PBX abroad: the emergency service will see the provider's address, not the venue's — keep a mobile phone nearby.
• The market codec is G.711. Exotel answers this directly in its FAQ: "use G.711 (india standard)", and the carriers list G.711 as their primary codec. That is exactly what our PBX accepts.

Who issues a number with a SIP trunk#

Exotel — the only trunk in the country with published parameters#

A Bengaluru cloud telephony platform holding a pan-India UL-VNO (Access Service) licence: its right to mix internet telephony with the public telephone network is its own, not rented. The product you need is Dynamic SIP Trunking: "SIP Trunking enables enterprise PBX, SBC, and SIP-based platforms to connect directly with Exotel's voice infrastructure using SIP over TCP or TLS", and the FAQ names Asterisk and FreePBX explicitly.

How to get it. Create an account at my.in.exotel.com → pass KYC (company PAN, certificate of incorporation or MSME registration, proof of address, photo of the signatory) → buy a number (they call it an exophone) → create a trunk → add your PBX's static IP to the whitelist → set your PBX address as the delivery point for inbound calls.

What to enter in the admin panel (Telephony → "Trunks and connections" → "Add provider"):

What to configure at the provider: pass KYC and buy a number → create a trunk and attach the number to it → add the static IP of your PBX (the "Server" tab) to the whitelist — without it outbound calls will not go out at all → set the PBX address as the inbound delivery point, with the port and the tcp transport → check that outbound calls present a valid number from your own account. Then use "Test connection", Lines and Outbound.

Pitfalls ⚠️

• Port 5070, not 5060 — the most common mistake when creating the trunk. And the transport is TCP, not the usual UDP.
• The whitelist is address based. Outbound calls only leave from the whitelisted IP: "your SIP server IP must be whitelisted … otherwise outbound calls will fail". Changing the PBX address breaks outbound calls silently — report a new address in advance when moving. A hostname instead of an address is accepted for inbound calls only.
• Ask support before you pay whether they will whitelist a PBX address outside India. Their documentation is written for Indian static addresses, while our PBX sits in the cloud. The whole design depends on the answer — this is the single open question about the country's best provider.
• The sending number is verified. On outbound calls the From header must carry a number purchased in the same account; any other number is cut off by the carrier.
• A default limit of 200 calls per minute per trunk — too low for outbound campaigns, raised on request.
• Inbound routing also lives on their side: a delivery address on the trunk is mandatory even when the call then goes into an Exotel flow.
• Media arrives on UDP ports 10000–40000 while the PBX accepts 10000–20000 — that is a subset, so no extra configuration is needed.

Source: Exotel — SIP Trunking, TCP (India) · FAQs · KYC — 10.09.2026.

TeleCMI / PIOPIY — a trunk with a login and password#

A Chennai platform: business telephony is sold under the TeleCMI brand and the developer interface under the PIOPIY brand. This is the only Indian provider found with an explicitly password-based scheme on the customer side: when a SIP endpoint is created, their system returns a username, a password and the gateway address of your namespace ("Your namespace SBC connection URL"). So the registration mode does exist technically, and every account gets its own address — there is no shared public hostname as with Exotel.

What to enter in the admin panel:

What to configure at the provider: open a PIOPIY account → pass KYC → buy a number → create a SIP endpoint (login, password, gateway address) → route inbound calls for the number to that endpoint → buy capacity for the number of simultaneous calls. The full list of questions for the manager is in "What to ask the provider".

Pitfalls ⚠️

• The documentation is written for applications and voice AI agents, not for an external PBX. Get written confirmation from support, before paying, that the endpoint works as a two-way trunk for an external PBX.
• The port, transport, codecs and number format are not published — request them as a parameter sheet at connection time and check them against the PBX requirements.
• There are two separate environments, Indian and international. Their addresses differ; make sure your account is opened in the Indian one.

Source: TeleCMI / PIOPIY India — create a SIP endpoint — 10.09.2026.

Carriers: Airtel, Jio, Tata Tele, Vi, BSNL#

For all five carriers a SIP trunk is not an "over the internet" service but a port on a dedicated link: the carrier builds the last mile to the venue's address, installs its own border gateway and router there, and hands over the trunk with private addressing inside its own network. A cloud PBX simply cannot enter that environment: there is no route from the internet to a 10.x.x.x address. Below is what the carrier puts on the order sheet, so that you know what to discuss with the manager and what would work if the PBX stood on the premises.

Bharti Airtel Business#

The largest private carrier; the product is advertised as "up to 30 simultaneous calls with just one number", with a number for every workplace. There are no prices or parameters on the site — only a request form. Onboarding: request → Airtel last mile → border gateway and router on site → trunk credentials.

⚠️ The domain Airtel expects in the From header is not ims.airtel.in, and it is often missing from the order sheet — request it separately. ⚠️ The outbound caller ID must be a valid Airtel number: "Outbound CallerID must contain valid AIRTEL DID or calls WILL FAIL".

Reliance Jio (JioBusiness)#

"IP based voice service that allows you to make and receive calls through IP-PBX over a single link", from 10 to 5,000 simultaneous sessions, a number per workplace, the 140XX range for telemarketing and self-service in the JioBusiness portal.

⚠️ Long-distance and international destinations are enabled by a profile on the trunk: "it does not call abroad" here usually means a disabled service rather than a PBX setting. ⚠️ The caller ID must belong to the allotted pool, otherwise the carrier rejects the call.

Tata Tele Business Services#

The leader in the small and medium business segment: "Replace outdated PSTN lines with a single, intelligent IP link", from 20 to 1,500 simultaneous calls, a start with 100 numbers, dual last mile auto-failover, a 99.5 % service level and G.711 voice quality. The trunk arrives as a separate four-address subnet: the gateway, the customer address and the carrier's SIP server address.

⚠️ Numbers are sold in solid blocks from 100, so "just one landline number" is not an option. ⚠️ There is no migration from an older digital line: a new SIP trunk order is required.

Providers that quote under contract: CloudConnect, Acefone, Ozonetel#

These providers do offer a trunk for an external PBX, but they do not publish the parameters — a manager hands them over after the contract is signed. That is why there is no "what to enter" table here: fill the form in from the sheet they send you, and take the list of questions from "What to ask the provider".

• CloudConnect Communications — "India's first licensed B2B Virtual Network Operator", a cloud telephony platform with SIP trunking, numbers and toll-free numbers, integration "with your existing PBX and UC platforms", prices from ₹699 per user per month. ⚠️ Their security description advertises TLS and SRTP — ask whether an unencrypted UDP or TCP option exists: our PBX will not accept an encrypted-only trunk. ⚠️ The per-user price refers to the cloud PBX — request the trunk as a separate line item.
• Acefone (Servetel until February 2025) — Indian cloud telephony on a DoT VNO-licensed network; SIP trunking sits in the solutions catalogue next to the hosted PBX and the voice API. ⚠️ A trunk for someone else's PBX is not their showcase scenario: sales managers steer you towards their own softphone, so state the task plainly. ⚠️ The company runs several support environments (Indian, UK and the old Servetel), so it is easy to reach the wrong one.
• Ozonetel — the CloudAgent contact-centre platform from Hyderabad. Its admin guide has "SIP Locations": the address of an external SIP server that handles a location's numbers is configurable. ⚠️ This is a contact-centre mechanism rather than a documented two-way trunk — confirm bidirectional calling and outbound with support. ⚠️ Billing is tied to agent licences rather than channels.
• Tata Communications (Global SIP Connect) and Knowlarity (Gupshup) are irrelevant for a single venue: the former is enterprise scale, with minimum commitments and connection through certified border controllers, while the latter is moving its line-up into Gupshup and publishes no trunk parameters.

International providers with Indian numbers#

Cards for the popular international providers are already in the catalogue when you add a provider — the server address and the mode are filled in for you. What is specific to India:

• Zadarma is the simplest way to get an Indian inbound number without an Indian legal entity: landline numbers in Bengaluru (080), Gurgaon (0124), Mumbai (022) and New Delhi (011) at $34 per month, and the international toll-free 000800 range at $80–90. The paperwork is a company registration certificate or a passport, proof of address no older than 6 months and a letter for the number connection; an address in any country is accepted. The mode is registration.
• DIDWW does sell local +91 numbers (Ahmedabad, Chennai, Gurgaon, New Delhi and others), but for India only inbound calls are supported: local SIP trunking, SMS, emergency calling, inbound fax and number portability are all marked as not supported. In practice the number is fine for receiving calls, while outbound has to leave through another trunk.
• Twilio offers no local Indian numbers at all: the only range available for the country is the toll-free +91800, and the owner's address must be outside India ("Must be outside of the country").
• Telnyx, Bandwidth, Infobip, didlogic — Indian numbering is not available from all of them and comes with country requirements; check availability and paperwork for your specific city before paying.
• Plivo, Kaleyra, Sinch — platforms of Indian origin or with a strong Indian presence; voice is sold through a programmable interface, and a trunk for an external PBX is a matter of contract.
• ⚠️ A caveat for the whole section. None of them is an Indian licensee: the number is issued through a local partner. That does not extend to outbound calls with an Indian caller ID — those are cut off by the government system that blocks spoofed international calls. The workable design, "inbound through an aggregator, outbound through an Indian licensee", means two separate trunks and two different caller IDs — warn the venue in advance.

Number porting#

• Mobile numbers can be ported between carriers across the country: the service has run since 2011 and has been nationwide since 2015.
• Landline number portability does not exist in India. The regulator has been asked to prepare recommendations, but as of 10 September 2026 the service has not launched. The practical conclusion: a landline number is tied to its carrier, and changing provider means changing the number — or keeping the old trunk in parallel for inbound calls.
• Numbers from international aggregators are not portable. DIDWW marks porting for India as not supported; porting back from a foreign aggregator to an Indian carrier is a question for the receiving side.
• The number is issued to a legal entity. The paperwork is corporate, so a number registered to an employee or to an integrator leaves with them when the relationship ends. Register it to the venue's company from the start.

Rules and paperwork#

If it does not work#

1. "Test connection" fails and the address looks like 10.x.x.x or ims.airtel.in. This is not a configuration error: all five carriers keep the handover inside their own networks, and there is no route to it from the cloud. The "cloud PBX plus a carrier trunk" design does not exist in India — either the PBX stands at the venue, or you use a provider from the first two sections.
2. Exotel does not answer the connection test. Check the port: theirs is 5070, not 5060, and the transport is TCP, not UDP. Both fields are edited in the trunk card.
3. Inbound works, outbound is rejected. With Exotel outbound calls are only allowed from a whitelisted address — compare the "Static IP" on the "Server" tab with what is registered in the provider's account. Re-check the address after a move or a change of server capacity.
4. The call leaves but never arrives, or the carrier returns a rejection. It is almost always the caller ID: it must be a number from your own account or pool. Leave the Show as field empty and the line's number will be used.
5. International destinations are silent while local calls work. With carriers the call types are enabled by a profile on the trunk — ask the manager whether long-distance and international calling are switched on.
6. The provider only offers TLS and SRTP (this happens with CloudConnect). Our PBX will not accept an encrypted trunk — ask for a plain UDP or TCP one, or choose another provider.
7. The number is written differently and the line is not matched. Not a problem: matching uses the last seven digits, so both +91XXXXXXXXXX and the form without the country code resolve to the same line.

Causes that are not country-specific are in "If calls do not go through".

Frequently asked questions#

Which provider should I start with?#

With Exotel: it is the only provider in India that publishes full trunk parameters (pstn.in2.exotel.com, TCP 5070, IP authentication, G.711) and keeps an Asterisk configuration example in its documentation. The order is: Indian legal entity → KYC → number → trunk → your static IP on the whitelist. Ask one question before paying: will they whitelist a PBX address outside India?

Can an Airtel or Jio number be connected to our PBX?#

No. Both deliver the trunk over their own last mile, with the border gateway on a private address inside the carrier's network — no configuration can create a route to it from the cloud. Their service assumes a PBX physically located at the venue. Do not accept a promise to "connect Airtel to your cloud PBX".

Is an Indian legal entity required?#

For a number from an Indian provider, yes: KYC is corporate (company PAN, certificate of incorporation or MSME registration, proof of address). Without an Indian registration the remaining route is international aggregators — Zadarma, for instance, accepts an address in any country — but that means inbound calls only.

Why can I not call out with an Indian number through a foreign carrier?#

Since October 2024 a government system at the country's border blocks international calls presenting a spoofed Indian number: a call from abroad showing an Indian caller ID is cut off. Outbound calls with an Indian number must leave through an Indian licensee — that is, through the same trunk that carries inbound calls.

What do I need to know about call recording?#

The 2023 data protection act treats voice as personal data: clear notice, the other party's consent, secure storage and deletion once the purpose is met are all required, and the maximum penalty is up to ₹250 crore. Enable the spoken recording notice in the location settings and make sure that a refusal is honoured.

Can I call guests from the PBX?#

Advertising and outbound campaigns in India run from the separate 140XX number range and follow the commercial communications rules — calling from an ordinary landline number is not allowed. Jio, for example, sells that range as a separate item. Service calls to a specific guest (confirming a booking, clarifying an order) are not covered by those restrictions.

Sources#

All links checked on 10.09.2026.

Providers with published parameters

• Exotel — SIP Trunking, TCP (India): https://docs.exotel.com/dynamic-sip-trunking/exotel-sip-trunking-tcp-india
• Exotel — Dynamic SIP Trunking FAQs: https://docs.exotel.com/dynamic-sip-trunking/faqs
• Exotel — SIP Trunking quick start: https://docs.exotel.com/dynamic-sip-trunking/exotel-sip-trunking-quick-start
• Exotel — KYC verification: https://docs.exotel.com/business-phone-system/kyc-verification
• Exotel — pan-India UL-VNO licence: https://exotel.com/newsroom/exotel-receives-licence-from-dot-for-pan-india-virtual-network-operator/
• TeleCMI / PIOPIY India — create a SIP endpoint: https://doc.telecmi.com/piopiy-india/docs/create-sip-endpoint/

Carriers and providers quoting under contract

• Bharti Airtel Business — SIP Trunk: https://www.airtel.in/business/b2b/landline/sip-trunk/
• Reliance Jio — SIP Trunk Services for Business: https://www.jio.com/business/services/voice-and-collaboration/sip-trunk/
• Tata Tele Business Services — SIP Trunk Solution: https://www.tatatelebusiness.com/voice-services/sip-trunk-services/
• Vi Business — Business SIP Trunking: https://www.myvi.in/business/business-communications/sip-trunking
• BSNL — SIP Trunk Service: https://www.bsnl.co.in/opencms/bsnl/BSNL/services/enterprises/Sip_Trunk_new.html
• CloudConnect Communications — Cloud SIP Trunking: https://cloudconnect.in/cloud-sip-trunking
• Acefone — SIP Trunking: https://acefone.com/solutions/sip-trunking
• Ozonetel — SIP Locations: https://docs.ozonetel.com/docs/sip-locations
• Tata Communications — Global SIP Connect: https://www.tatacommunications.com/solutions/unified-communications/global-sip-connect/

Regulator and international numbers

• DoT — National Numbering Plan 2003: https://dot.gov.in/access-services/national-numbering-plan-2003
• DoT — Revised Guidelines for Other Service Providers, 23.06.2021 (PDF): https://www.dot.gov.in/static/uploads/2025/08/4e6e21029dc45f42b4e1e57e6300fa72.pdf
• Launch of the International Incoming Spoofed Calls Prevention System, 22.10.2024: https://www.newsonair.gov.in/international-incoming-spoofed-calls-prevention-system-launched
• Twilio — India regulatory guidelines: https://www.twilio.com/en-us/guidelines/in/regulatory
• DIDWW — India local numbers and the capability matrix: https://www.didww.com/phone-numbers/local-numbers/India/Local
• Zadarma — Indian virtual numbers: https://zadarma.com/en/tariffs/numbers/india/

Related pages#

• Connecting a provider's number to the PBX — the common steps, trunk modes, networking and the connection test.
• Setting up SIP phones — how to connect desk phones and DECT to extensions.