What is a PRI trunk?
A PRI (Primary Rate Interface) trunk is a type of digital circuit commonly used by call centers, sales offices, and businesses that handle large volumes of phone calls. Each PRI circuit provides up to 23 voice channels, allowing multiple concurrent calls to be placed or received over a single connection.
To use a PRI, businesses need an on-premises phone system equipped with a PRI card. While once considered the standard for enterprise telephony, PRI is gradually being replaced by more flexible, cloud-based options.
Key features of PRI systems
High call capacity – up to 23 simultaneous call paths per circuit.
Direct Inward Dial (DID) support – employees can receive calls directly without routing through a central menu.
Fax compatibility – PRI circuits can be configured to support digital fax lines.
Stable and reliable – PRI circuits are dedicated connections known for consistent performance.
The shift away from PRI
Although PRI systems remain in use, most businesses today are transitioning to cloud-based phone systems or SIP trunking. These solutions offer:
Easier scalability (add or remove users instantly).
Lower costs with no on-premises PRI hardware.
Advanced features like call routing, voicemail-to-email, and mobility support.
Simplified management with everything hosted in the cloud.
Looking for business phone service? Compare providers and see your options instantly.