As you research phones for the office, you’ll come across a type of phone known as an IP phone. These devices are also known as SIP phones. SIP phones aren’t anything like analog-based antiques of the past  — they work exclusively over the internet. 

In this guide, we’ll explain exactly what a SIP phone is, how it works to make phone calls, and which models are likely to work best for you. 

But first, let’s explain a couple of quick definitions and meanings around these IP phones.

What Is a SIP Phone?
A SIP phone is a device that uses the internet to make and receive phone calls. Instead of relying on traditional phone lines, SIP phones use a technology called Voice over IP (VoIP) to transmit voice data over the internet. This allows for a number of benefits over traditional phones, such as lower costs, advanced features, and wideband audio (HD voice). 

There are two types of SIP phones: hardware and software.