Free SIP trunks: Do they exist?
One of the most common questions you’ll see when researching cloud communications is about how to get a free SIP trunk.
This kind of question is pretty common, but it doesn’t come without complications.
But considering it’s such a common question, we thought we’d go through the basics of what you’re getting when you pay for SIP trunks and what a “free” SIP Trunk actually is.
What is a SIP trunk?
We give a pretty good description of what a SIP trunk in our guide, but what we’ve found over the years is that in the telecoms industry there’s no single, simple definition.
Explaining it can get pretty complicated pretty quickly. But all you need to know is that a SIP trunk allows you to transfer your voice data in the same way you transfer your data over the internet.
Calls, capacity, and cost
If you’ve done a bit of research into SIP trunks, you’ll notice that they typically come with a certain amount of channels.
Think of a channel as the bandwidth needed to make one call on our network. The more you have, the more concurrent calls you can make at any one time.
If you’re used to purchasing in the telecoms space you’ll be comfortable with the concept of channels and understand why they tend to come in batches.
In the days of PRI ISDN, these were usually bundles of around 20-30ish.
But because SIP trunks work over IP networks, there’s a lot more flexibility when it comes to increasing your capacity, with SIP trunk providers able to adjust the number of channels you need in almost real-time.
Not only that but unlike the limitations from copper lines, a SIP trunk can have an unlimited number of channels. You have to pay more obviously, but you can have as many as you want to pay for.
“Buying” a SIP trunk
When you buy a SIP trunk, what you’re actually buying is access to a SIP trunk and its connection to your PBX.
Weird right? Think of it like your contract for your mobile data. You don’t own the connection to the internet, you’ve just gained access to the network you have your contract with.
Now you know what SIP trunks and channels are, the business-savvy among you will be able to work out how most providers price them up.
Typically, you pay once for SIP trunk access, then for the number of channels you need to support your call traffic.
So if you need to have 10 calls going on at any one time, you’re going to need 10 channels.
On top of that, most providers charge for individual number usage and for the number of minutes you use.
The “free” SIP trunk
So if all of the above is the case industry-wide, why do so many companies offer “Free” SIP trunks? Well, the main reason is that it’s a valuable marketing tactic that gets people interested.
But on the whole, it’s actually true. Like we said above, it isn’t the SIP trunk you technically pay for, but the usage.