What is a SIP Trunk? : Operation and Advantages

Manage your company's communications, gaining efficiency and savings at the same time. VoiceToPhone offers you sip trunks to make and receive calls with unlimited capacity of simultaneous voice channels, support for multiple codecs, with sip and IP interconnection.

What is a SIP Trunk?

Sip trunks are really telephone lines that work through the internet using the SIP protocol. The SIP trunk is a communication connection that links with public telephony to provide one or more voice channels bidirectionally (incoming and outgoing calls) therefore they can be associated with DID virtual numbers and can also be connected to virtual pbx, physical telephone exchanges or plants and call centers.



Sip Trunk vs Analog Telephony


SIP trunks and the upgrade to new cloud telephony systems are inevitable in the near future. Large telecommunications and internet service providers are migrating their clients from the old analog or traditional telephony to the new IP telephony. Sip trunks or virtual telephone lines, unlike the old PSTN or old telephony that was delivered in physical wiring, offer a more comprehensive, modern service, with economic advantages, and also have greater flexibility at the time of contracting.


How does a SIP trunk work?


The Sip trunks or "Sip Trunks", commonly work to allow the link or virtual connection between a telephone exchange, belonging to a company or user, and the telephone network of a Voip or Ip telephone provider, through the Internet. Sip trunks offer incoming and outgoing calls within their main functions, and today they allow linking landlines and mobile numbers (DIDs) to receive calls depending on the coverage of each country.

Link your telephone Phone system with our Sip Trunk service and take advantage of its advantages



Savings of more than 60% in telephone billing and 100% in technical resources .


Unlimited availability of incoming and outgoing channels as needed.

DID Numbers

Add virtual numbers from any country to your telephone exchange.


Easy integration with any Ip telephone plant or Gateway .



Do not limit yourself! Our Sip Trunk offers you much more..

Our sip trunk service offers practically unlimited capacity for incoming and outgoing channels so that you can answer your calls as often as you need. In just minutes we activate the number of channels that will help you grow without limits! , and with the possibility of expanding your business communications globally. Voicetophone delivers a unified sip trunk service with everything you need:


High call quality

SIP traffic is delivered with high audio quality, high ASR and long ACD so your customers get the best calling experience.


Availability and Reliability

Our availability is ultra high, with constant traffic monitoring to achieve the highest quality and reliability.

Transparent billing

Monitoring tools with call histories, costs, filters, etc. are provided in a CDR portal for each SIP trunk.


Make and answer your calls from anywhere with our sip trunk (connected to a virtual PBX or telephone exchange).

Start working with our SIP Trunk solution

Instantly, without contracts or permanence


Frequent Questions

What do I get with the SIP trunk service for my company?

With the SIP trunk service you will obtain a link that will allow you to connect our telephone service with your telephone exchange, telephone plant or call center to make or receive calls with a SIP connection at low costs, and with the number of simultaneous channels as required.
Our connection is through authentication by Ip address or by username and password if you do not have an established Ip address.

How do I get a free trial?

It is very easy, please fill out the contact us form and request a free trial or demo so you can test the quality of our service.
We usually provide a sip trunk for outgoing calls with a small balance enough to make several calls.

What are the prices per minute for outgoing calls?

We only have sip trunks with high call quality.

We handle minute plans that vary according to the country of destination. Another factor that influences the cost per minute is the amount, please contact us for more information.

Can I associate one or more DID numbers to a Sip trunk?

Yes, to receive calls you can associate one or several virtual numbers (DIDs), and even from different destinations in the same trunk of outgoing calls. Both channels (incoming and outgoing) will be used independently on the same trunk.
You can review the cost of each virtual number you wish to associate here.

What do I need to start using the SIP trunk service?

To start using the service you need the following:

  1. Create a sip account and buy a plan of minutes that will be used in the trunk.
  2. A PBX phone system or physical telephone plant with SIP connection.
  3. An IP address, if IP authentication is required.
  4. Internet connection, preferably broadband.
  5. Computers or smart mobile devices to make or receive calls.

What happens if the contracted minutes in the plan run out?

No problem, you can ask your sales advisor for an additional package of minutes or increase the contracted plan. The important thing is that you do not lose continuity in the service.

Do you offer annual payment discounts?

Yes, we offer discounts of 15% for early payment of one year, please contact your trusted advisor.

Can I record all the calls generated in the sip trunk?

Yes, to obtain the recording service you must request it and add it to the contracted plan. This service has an additional cost.

What means of payment do you accept for the payment of services?

We accept payments through bank transfer and Paypal. For more information, please contact your trusted advisor.