This article explains the difference between Busy and Call Waiting, and what happens when a user receives another incoming call while they are already on a call.

The behaviour of the second call will depend on whether Call Waiting is enabled or disabled for the user.

Busy

A user is already on a call and cannot accept another incoming call.

When a second call is made to that user:

• The caller may hear an engaged/busy tone.
• The call may be sent to voicemail.
• The call may follow a busy destination or forwarding rule.
• The user is not notified of the second call.

Example

• Extension 100 is on a call.
• Call Waiting = Disabled
• Another caller rings Extension 100.

Result:

The caller receives a busy response, voicemail, or busy forwarding.

Call Waiting

A user is already on a call but is allowed to receive additional incoming calls.

When a second call arrives:

• The user receives a call waiting notification (tone, popup, or visual alert).
• The user can answer the second call.
• The user can place the first caller on hold and switch between calls.
• The caller does not receive a busy tone.

Example

• Extension 100 is on a call.
• Call Waiting = Enabled
• Another caller rings Extension 100.

Result:

The user is notified of the new call and can choose to answer it.

Comparison

Typical Business Use

Busy

• Reception phones without multiple call handling.
• Users who should not be interrupted.
• Busy destinations routing to voicemail or assistants.

Call Waiting

• Managers, sales teams, receptionists and support staff.
• Users who need to handle multiple calls simultaneously.

Key Difference

Busy means the extension is unavailable because it is already on a call.

Call Waiting means the extension is already on a call but can still receive and answer additional calls.