Glossary
DID
Direct Inward Dialing gives a person, a department or a location its own public phone number on the same phone system as everyone else. Callers reach them directly without pressing anything.
A DID, or Direct Inward Dialing number, is a public phone number that rings a specific destination on a business phone system, such as one person's extension, a department group or a branch office, without going through the main menu. In VoIP services the term is often used simply to mean any phone number assigned to the system. A business typically has one main number plus as many DIDs as it needs.
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What it means
The term comes from the era of PBX trunks, when a block of numbers could be delivered over a few shared lines and the PBX used the dialled digits to ring the right desk. The idea survives unchanged: a public number maps to an internal destination. What has changed is that with a cloud phone system each number is an entry in a table rather than a wiring decision, and any number can point anywhere.
In practice, VoIP providers use 'DID' loosely to mean a phone number on the service. A local number, a second number for a marketing campaign, a number for the Montréal office: each is a DID. The main number is a DID whose destination is the main menu.
How it is used in a business phone system
- A direct line for a senior person or a key account manager so regular contacts skip the menu.
- A separate number per location, each with its own greeting and hours, all on one system.
- A number for a campaign or advertisement, routed to a sales group and reported separately in call analytics.
- A dedicated fax number delivered to online fax rather than a machine.
How 3CTel uses it
3CTel provides Canadian local and toll-free numbers and ports existing ones. Each number is assigned a destination in the hosted system: a menu, a person, a ring group, a queue, a fax service or the AI receptionist. Outbound caller ID is set so calls from a department show that department's number. A specialist plans the numbers with you and confirms which existing ones to port and which new ones to add.
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Learn more: Call AnalyticsCommon questions about DIDs
Does every employee need their own DID?
No. Most staff are reached by extension through the main number or a department group, which is simpler to manage and keeps the public number list short. Direct numbers are worth giving to people who deal with outside contacts regularly, to locations, and to functions that benefit from separate reporting such as sales or a fax line.
Can one DID ring more than one place?
Yes. A DID points to a destination on the phone system, and that destination can be a ring group, a queue or a rule that rings different places by time of day. A single number can ring the office during hours and a cell phone app after hours, or ring two locations at once and connect whoever answers first.
Related pages.
Business Phone Numbers
Local, toll-free and campaign numbers that all land in one system.
Learn more: Business Phone NumbersOnline Fax
Fax by email and web — without keeping a dedicated phone line alive.
Learn more: Online FaxLocal vs toll-free numbers
Which number goes on the sign, which goes on the website, and why the answer is often both.
Learn more: Local vs toll-free numbersNot sure which of these you need?
Describe how your calls arrive today and a 3CTel specialist will map them to the right pieces, build them on a temporary number and quote the result before anything is billed.