Wholesale SIP Services

Wholesale SIP


Service we offer


Origination (Inbound)

Vox Tandem provides reliable inbound access for carriers through a SIP-based hand-off. Our DID (direct inbound dialing) origination services provide you with access to numbers in many U.S. markets which are available for instant provisioning.


Toll Free Origination

Vox Tandem now offers Toll Free number access across the entire United States and Canada. We transport Toll Free traffic originated by cable, VoIP, traditional landlines and wireless carriers to all major inter-exchange carriers in the U.S. and Canada.


Termination (Outbound)

Vox Tandem offers a completely managed and customizable VoIP carrier solution. We provide a reliable and fully-redundant, carrier-grade termination service on one of the industry's most extensive voice networks. Our outbound service, which currently supports G.711 and G.729 codecs, allows you to take full advantage of the best available call quality.


Toll Free Termination

Vox Tandem offers FREE Toll Free Termination service for all your calls in the United States! Our FREE registrationless call termination delivers guaranteed superior call quality, service, and reliability by utilizing our nationwide network of partners, unlike many free services offered by other online providers.


LRN Query

One Query to Rule Them All! Vox Tandem offers our unique LNP / LRN Query solution with benefits such as SIP302 Redirect Unlimited, webAPI, high volume query capability, 24/7 Monitoring and NO monthly minimum commitments!


E911 Emergency Service

Vox Tandem helps SIP trunking providers meet these objectives with cost-effective solutions that provide accurate E911 capabilities for subscribers both inside and beyond the provider's service footprint. With one of the largest E911 coverage in the industry, we serve subscribers across the US, helping meet all FCC regulations.

Free Testing Account