Call forwarding
Call forwarding is a telephony feature that redirects an incoming call from the number or endpoint originally dialed to another destination according to a configured rule.
The destination can be another phone number, a contact center, a voicemail box, a SIP endpoint, or a service that answers calls. Forwarding may apply to every call or only under defined conditions, such as no answer, a busy line, after-hours coverage, or a network failure. The original caller normally stays on the same call while the telephony network creates the route to the new destination.
Businesses use forwarding to preserve an established public number while changing where calls are handled. A company can forward an existing line to an AI phone agent, route overflow traffic to another team, or send after-hours calls to a separate flow. This is different from number porting: forwarding leaves the number with its current carrier, while porting moves control of the number to another carrier.
For AI phone calls, forwarding is often the bridge between existing telephony and a new agent. The business keeps publishing the same number, then changes a carrier or phone-system rule so calls reach the agent. The setup should preserve the caller's identity where possible and avoid loops in which the agent or fallback destination forwards the call back to the original route.
Call forwarding is also different from call transfer. Forwarding usually happens as part of inbound routing before a conversation begins. A transfer occurs after a call has already been answered and moves the active caller to another recipient. A cold transfer connects the caller without a private handoff, while a warm transfer can brief the recipient first.
Before launch, teams should test successful calls, unanswered destinations, busy conditions, after-hours rules, and failure routes. They should confirm which number appears as caller ID, whether the original dialed number remains available to the receiving system, and who controls voicemail. Billing can involve more than one call leg, depending on the carrier and route.
A simple forwarding rule can be reliable, but layered rules across a carrier, PBX, and application can become difficult to trace. Document the order of evaluation and keep a safe fallback destination so callers are not trapped in repeated forwarding or disconnected without an explanation.