SIP trunk cost calculator
Enter your monthly minutes and the two prices. See which pricing model costs less, and where they break even.
Use any currency: enter both prices in the same one. The starting prices are placeholders, so use your provider's quotes.
Per-minute pricing is cheaper by 50.00 a month.
Your channels would be busy about 4.6% of the time if you used them all month. Per-channel pricing pays off when channels stay busy. Not sure how many channels you need? Use the Erlang B calculator.
How the comparison works
SIP trunk providers usually sell in one of two ways. Metered pricing charges for each minute you use. Per-channel pricing charges a flat monthly fee for each simultaneous call you can make, with calling included. The calculator multiplies your minutes by the per-minute rate, multiplies your channels by the channel price, and shows which is lower.
Break-even
The break-even is the channel price divided by the per-minute rate: the number of monthly minutes above which the flat plan wins. Below it, pay by the minute.
Channel utilisation
One channel can carry at most 43,200 minutes in a 30-day month. Most channels carry far less, because calls bunch up in the busy hour. A low utilisation figure means you are paying for capacity you rarely use. To size the channel count itself, use the Erlang B calculator.
Limits
The calculator ignores number rental fees, taxes, international and mobile rates, minimum commitments and the fair-use terms that often come with “unlimited” plans. Read those before you decide. For the basics, see SIP trunking explained.
FAQ
What is a SIP channel?
One simultaneous call. A trunk with 10 channels can carry 10 calls at the same time.
Is unlimited calling really unlimited?
Often it comes with fair-use terms, exclusions for some destinations such as mobiles and international numbers, and a cap on concurrent calls. Read the terms for the countries you call.
Which is cheaper for a call center?
It depends on how busy your channels are. High, steady call volume tends to favour per-channel plans, while low or uneven volume tends to favour paying by the minute.