The three standard integration patterns
The simplest integration is conditional call forwarding. The operator keeps their existing business number with their existing carrier and configures the line to forward to the AI provider's number on no-answer, busy, or after hours. This requires no carrier change and is reversible.
The second pattern is SIP trunking. The AI provider becomes the SIP endpoint and routes calls to the operator's existing extensions after the AI handles the initial conversation. This works well for VoIP systems including RingCentral, 8x8, Vonage Business, and similar platforms.
The third pattern is full porting. The operator transfers ownership of the business number to the AI platform, which then becomes the primary carrier of record. This consolidates billing and removes the forwarding layer, but is more disruptive to undo.
What kind of phone system is compatible
Modern VoIP systems including cloud PBX platforms, traditional analog lines with forwarding capability, and mobile business numbers all work with AI receptionists using the conditional forward pattern. Legacy on-premises PBX systems may require a SIP gateway or a port to a cloud number. Cellular-only operators (food trucks, mobile service providers) can forward their mobile number directly.
What integration does not require
Operators do not need to buy new hardware. They do not need to change their existing carrier. They do not need to retrain staff on a new phone interface. The team continues to receive transferred calls on the phones they already use, whether desk handsets, softphones, or mobile devices.
Timeline and downtime
A conditional forward setup typically takes one to two business days from contract signature to first live call. SIP trunking integration takes two to five business days depending on the existing VoIP platform. A full number port takes seven to fourteen business days because it involves the losing carrier and FCC porting rules. Downtime during any of these is minimal if the integration is staged correctly.
When integration gets harder
The integration is harder for operators with: multiple business numbers across different carriers, contact-center platforms with custom IVR trees, fax-over-IP requirements, or strict on-premises telephony with no SIP capability. In those cases, the AI provider's implementation team usually proposes a staged rollout.