SIP TRUNKING

International calling made simple with unified communications. Drive workforce productivity through our reliable SIP trunking services.

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MOVING TO SIP IS EASY

Enterprises looking for interoperability with legacy systems can transition seamlessly to this VoIP solution. SIP trunking services enable the integration of your critical business communication functionalities over a single IP connection, improving your collaboration and infrastructure efficiency.

GTT SIP trunking drives productivity and efficiency by integrating diverse communication capabilities onto a single global platform for your business. We help you create custom APIs for your SIP trunking needs. Make real-time calls with Session Initiation Protocol today.

The Benefits of GTT SIP TRUNKING

SIP trunking is more than just making phone calls to and from anywhere—it’s about connecting globally with your business phone system. With GTT as your SIP trunking provider, you can trust that you’re getting the most secure phone system that works with any legacy IP PBX system.

Easy Integration

SIP trunking services easily integrate with any mix of legacy telephony equipment for expanded telecom capabilities. GTT trunks between the internet and PTSN for optimal business communications.

Reliable SIP Service

Our business communication SIP trunking ensures high-quality calls are possible at all times. Run your VoIP services over SIP trunks for reliable and secure calling.

Cost Effective

GTT pricing was designed with global enterprises in mind. We offer free office-to-office calls and a single global cost model.

Global Reach

Make calling and messaging business contacts and clients across the globe convenient and secure. Inbound and outbound global calling enables your business to thrive. With SIP trunking and centralized global provisioning, internet connectivity and outages will not affect call quality.
Global coverage
Global SIP Trunking footprint

COMPREHENSIVE GLOBAL FOOTPRINT

We offer a full suite of international services, including DIDs, toll-free, termination, and emergency services, providing expansive reach on a global basis. Enable call recording to store previous conversations for your business.

Our global, fully redundant, and robust SIP-based network has been specifically designed to meet the demands of your bandwidth-intensive communication services. With a network of virtual phone lines, you can extend your global reach without sacrificing functionality or price.

DRIVE COST SAVINGS

SIP trunking is capex-efficient and easily integrated with our SD-WAN, MPLS or Internet services, eliminating the need for public switched telephone network (PSTN) gateways and ISDN BRIs or PRIs.

The service also reduces local and long-distance costs, with site-to-site calling included at no charge. Managing outbound calling is simple, as calls are charged from a single, shared rate card for all sites.

Guaranteed security for your business

WHY GTT
SIP TRUNKING?

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Diverse global communications services integrated into one cloud-based connection. Eliminate the need for landlines.

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Interoperable with key UC platforms and legacy infrastructure. Supports direct routing to CRM platforms, Microsoft Teams, Cisco Webex Calling & Zoom Phone apps for video conferencing and instant messaging.

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Global SIP-based voice network includes industry-leading Session Border Controllers for easy scalability.

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Comprehensive telephony footprint with DIDs in 55+ countries and toll-free numbers in 120+ countries.

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Low latency global outbound calling using our IP backbone to deliver locally terminated calls.

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Free office-to-office calls on-premises.

FAQs

When trying to find the best SIP trunking provider, consider factors such as reliability, geographic coverage, uptime, pricing, customer support, and compatibility with your existing system (all of which GTT SIP trunking solution offers!).

Yes—many providers (including GTT) allow you to port existing phone numbers to keep your well-established business numbers for voice calling and SMS texting.

Security measures like encryption and authentication are typically employed to protect SIP trunking traffic. Monitoring your business phone service has never been easier.

TRUST GTT AS YOUR GLOBAL
SIP TRUNKING PROVIDER

We pride ourselves on our seamless SIP trunking services that simplify global communication for our customers. If you are an enterprise or contact center seeking a secure and reliable telecommunications solution, reach out to us today.

Related Services

Google SIP Link

Use Google desktop features and integrate GTT voice communications with Google SIP Link.

Managed SD-WAN

Transform your WAN with dynamic network traffic management. SD-WAN technology benefits include flexibility, speed, security and cost control.

Dedicated Internet

High-quality internet connectivity for enterprises, delivered on our leading Tier 1 IP network.

MPLS

High-performance, secure connectivity for your global enterprise, backed by end-to-end SLAs.

Cloud Phone Direct

Global, scalable & High-Performing Enterprise Voice Services

Virtual Voice Network

Easily expand your global voice footprint without making large upfront infrastructure investments

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Explore our collection of videos, research, guides and more with invaluable insights into our digitally networked world.

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Our Gartner rating

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Global WAN Services

4

 
 

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As of 13 May, 2026

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