Modern telephony. Built on what you already have.

Ready to elevate your communications? Take your first step toward cloud-based communication with NFON SIP Trunk - a flexible, scalable, and secure VoIP telephony solution tailored for modern businesses.

Maximised flexibility
Hassle-free integration
Reliability and Built-In Failover

SIP Trunk unleashes flexible communication.

Our SIP Trunk gives you maximum flexibility while keeping your existing communication setup. Keep your PBX, keep your phones – just add powerful VoIP. From international numbers to smart routing and certified interoperability, NFON SIP Trunk simplifies your telephony, reduces costs, and lets your business scale without complexity.

SIP Trunking that fits your business.

Europe-wide availability.

A telephony solution for businesses with multiple locations and phone numbers across Europe — supported by local teams.

Flexible number routing.

Easily route numbers from one block to multiple PBX systems without the cost or complexity of acquiring new number ranges.

Cost-efficient.

Eliminate redundant tasks with pre-configured bots that detect common customer issues, saving you the manual work of training.

Certified phone systems.

We’re tested and certified with a wide range of PBX providers — ensuring smooth integration without technical hurdles.

SIP the Trunk the way you want.

Centralise and simplify communication.

SIP Trunking allows businesses with multiple locations to consolidate their telephony into a single, unified system.


Instead of managing separate PBX installations, voice channels, numbers, and settings can be centrally administered via one portal — reducing technical complexity, lowering operational costs, and simplifying administration.


New locations can be added quickly without the need for separate trunks, enabling greater efficiency and seamless scalability.

More possibilities through integration.

SIP Trunking enables businesses to enhance Microsoft Teams* with powerful telephony features — via Direct Routing or Operator Connect. Employees can make internal and external calls directly within the familiar Teams interface, without any additional hardware or software.


At the same time, SIP Trunk can be integrated into contact center solutions like NFON Contact Center Hub or Genesys CloudCX. This ensures seamless PSTN connectivity for customer interactions, improves reachability and service quality — all while using your existing infrastructure.

Efficient number management

With our SIP Trunk, businesses can flexibly assign available numbers across locations and PBX endpoints — all centrally managed through one portal. As long as capacity exists within an existing number block, there's no need to purchase additional ranges.


Numbers can also be quickly reassigned as needed — for example, during office relocations or seasonal shifts.


This gives businesses full control over their number resources, helping them stay reachable, agile, and cost-efficient at all times.

Optimised load distribution for teams and locations

SIP trunking helps businesses route calls flexibly and reliably across phone systems and locations. With high availability options, you stay reachable even during outages or peak times: calls can be automatically redirected to a backup system (Primary/Backup), rotated between systems (Round Robin), or delivered to multiple PBXs in parallel (Forking).


This ensures better use of existing capacity, reduces wait times, and keeps communication stable — ideal for businesses with complex infrastructures or distributed teams.

Certified telephone systems and devices.

See how others are succeeding with NFON.

"Instead of having different PBX systems for each location, we can now use one single, easily scalable communication solution. The integration of Cloudya has given our teams a lot more flexibility."

Tobias Armleder

IT Lead, Demeter

“Since we switched to NFON, we can finally take calls wherever we are and from any device. The integrations with Microsoft Teams have made things a lot easier, and we can use the whole Microsoft Teams suite, with any client or partner - just being a click away at all times.”

Jeanne Beck,

Marketing Manager, Wefapress

Our biggest challenge is to stay connected at all times. That’s why telephony is a key priority for us. NFON offered us a cloud communication platform that can cover all our needs. Thanks to Cloudya’s seamless integration with Microsoft Teams, we can now make calls directly from the app and benefit from streamlined workflows and insightful reporting with Nmonitoring Queues.”

Fritz Pschormeir

Head of IT Infrastructure, financial.com

““I would recommend NFON without reservation – I just plug in a new device, and it works.”

Dominic Muskulus

Head of IT

Frequently Asked Questions.

Do I need new hardware to use SIP Trunk?

No, SIP Trunk integrates with your existing PBX systems and supports on-premise connectivity.

Can I keep my current phone numbers?

Yes, our flexible number routing allows you to retain and assign your existing numbers without purchasing new blocks.

Is customer support available?

Absolutely, our support team is available 24/7 to assist you.

How does SIP Trunk enhance security?

We prioritize security with features like call blocking and fraud detection to protect your communications.

Ready to get started? Let's do this