Direct Inward Dialing (DID) is when a telephone service provider connects a block of telephone numbers to your company's Private Branch Exchange (PBX).

Why use a DID number?

What is the advantage of having a DID route your calls through a PBX system? The benefit of having a DID is that any person can call the extension, or phone number, in order to connect to the recipient without having to go through a switchboard or operator and without the company having to purchase bulk phone lines.

What is a DID phone line?

Direct Inward Dialing (DID) is a communication technology designed to connect a set of external telephone numbers to a private branch exchange (PBX). Using DID technology, telephone numbers can be assigned dynamically throughout a company without additional external phone lines.