When your sales executive calls a customer, the number on the customer’s phone decides a lot. A random or unknown number often goes unanswered or gets marked as spam. A known company number gets picked up, and the customer can call straight back to the right team. That number is the outbound caller ID, also called CLI (calling line identification). This guide explains how outbound caller ID works on an IP PBX, how to plan it for an Indian business, and the rules you need to follow.
What outbound caller ID is
Outbound caller ID is the number your phone system presents when it makes a call to the outside world. Operators carry it to the person you are calling, who sees it on their phone and in their missed calls.
On an older EPABX, every call usually showed the main pilot number of the line. On an IP PBX with a SIP trunk or PRI, you can present different numbers for different people or departments, as long as the numbers belong to you.
Why the right caller ID matters
- More calls answered: customers answer a number they recognise, or one they can look up as your company.
- Call-backs reach the right person: if the accounts team calls from the accounts number, a customer who calls back reaches accounts, not reception.
- Less spam marking: calls from a consistent, genuine business number are less likely to be reported as spam.
- Clean records: the number the customer saw matches your call reports.
Indian rules for caller ID
Caller ID in India follows telecom licensing rules. In general:
- Present only numbers allotted to you. The caller ID must be a number your operator has given your connection, such as your pilot number or one of your DID numbers. Showing someone else’s number, or a made-up number, is not allowed.
- The operator decides what passes. On a SIP trunk or PRI, the operator checks the number your PBX sends. If it is not on your connection, the operator may replace it with your pilot number or reject the call.
- Telemarketing is separate. Promotional calls must come from the number series set aside for telemarketing, not from ordinary business numbers, and must respect customers’ TRAI DND preferences.
Rules and operator practice change from time to time, so confirm with your operator which numbers you may present on each trunk. For a primer on direct numbers, see DID numbers in India.
Where caller ID is set in Voxdial IP PBX
Voxdial IP PBX lets you set the outbound caller ID at three levels:
| Level | Setting | Typical use |
|---|---|---|
| Trunk | Outbound caller ID (the trunk’s default) | The pilot number of that SIP trunk or PRI line |
| Outbound route | Route CID | A number for all calls using one route, for example a branch number |
| Extension | Outbound CID and emergency CID | A person’s or department’s own DID |
Each extension also has a display name, which shows on internal calls so colleagues see who is calling.
The emergency CID on an extension is the number sent on emergency calls. Set it to a number that leads back to that site, so emergency services can call back the right building.
When more than one level is set, test which number the called phone actually shows, and keep the setup simple so everyone understands it.
Planning caller ID for your company
Small office
One pilot number for everyone, set on the trunk. Customers call back to the IVR or reception and are routed from there.
Departments with their own numbers
Give sales, accounts and support their own DIDs, and set each extension’s outbound CID to its department number. Call-backs go straight to the department’s ring group or queue.
Individual direct numbers
Senior staff, doctors or relationship managers can have a personal DID as their extension’s outbound CID, so customers can reach them directly.
Branches and multiple trunks
If a branch has its own trunk, set the trunk caller ID to the branch number. If calls can overflow from one operator’s trunk to another, make sure a valid number from the second operator is set too, so overflow calls are not rejected. Least cost routing explains how routes and trunk sequences work together.
Call centre
For Voxdial Contact Center, present a number that leads back to the right queue. If a customer misses the call and calls back, they should land in the same team, not a general IVR.
Common caller ID problems
| Problem | Likely cause | What to check |
|---|---|---|
| Customers see the main number, not the DID | Operator replaces numbers it does not recognise | Confirm the DID is on that trunk’s connection and in the format the operator expects |
| Calls fail when a caller ID is set | Number not allotted on that trunk | Use a number from that operator, or the trunk’s pilot number |
| Wrong number shows on overflow calls | Second trunk has no valid caller ID | Set a valid default caller ID on every trunk |
| Customers do not answer | Number unknown or marked as spam | Use a consistent business number and avoid frequent changes |
If spam-labelled calls are a concern from the other side, see how to block spam calls on a business phone.
Want caller IDs planned for your departments, branches and trunks? Talk to BitVoice.
FAQs
What is outbound caller ID?
It is the number your phone system shows to the person you call. On an IP PBX it can be set per trunk, per route or per extension.
Can I show my mobile number as caller ID from the office phone system?
Only if your operator allows that number on your trunk. In India the caller ID must be a number allotted to your connection, so check with your operator first.
Can each employee have their own caller ID?
Yes, if each has a DID from your operator. In Voxdial you set the DID as the extension’s outbound CID.
Why does my DID not show on outgoing calls?
Usually the operator does not recognise the number on that trunk, or it is in the wrong format, so it substitutes your pilot number. Check the number is allotted to that connection.
