If you’re wondering how this phone service works in practice from an admin perspective, we send a pro-forma invoice to the email address for the account.

This happens five days before you’re charged the monthly recurring fee. We bill you at the beginning of the month for the new month you are entering.

The only arrears billing happens with the per-minute charges for our SIP unmetered plan or any toll-free calls to your Nextiva SIP trunk account.

If you’re looking at your current PBX bill and comparing it to the above numbers, you already know what makes SIP trunking affordable. (In that case, you also may want to pull your hair out because of the money you’re throwing away.)

Here are the reasons why SIP trunking is so affordable:

• There’s no need for expensive POTS (short for Plain Old Telephone Service) lines
• Lower cost of per-minute calling, even on metered plans
• Free calls between your employees and offices
• It maximizes your existing phone system and connecting it to a cloud PBX

If your company is growing, a traditional phone system will actually punish you for that. Hiring more people means adding more phone lines.

With PRI (Primary Rate Interface), you’re using a traditional phone line to make phone calls. Each PRI circuit allows for up to 23 simultaneous calls. If you need more, you have to buy PRIs in bundles of 23 channels at a time.

Your bill becomes unnecessarily high because you’re paying for a number of channels you don’t need. This system doesn’t give you flexibility or predictability in your recurring or upcoming expenses. It makes scaling particularly difficult if you’re growing your call center.

SIP trunks make it easy to upgrade to a higher plan at any time. You can add more concurrent calls (also known as SIP channels) and phone numbers in real-time.