Premium Plus VoIP Rates

The Premium+ Route bypasses resellers and intermediary carriers entirely, routing traffic exclusively through direct bilateral interconnect agreements with Tier-1 telecom operators. This means every call takes the shortest, most reliable path from VoiceBuy’s switching infrastructure directly to the terminating carrier — with no LCR shortcuts, no third-party hops, and no quality compromise. The result is maximum ASR (up to 65%), full CLI transparency, and SLA-backed performance guarantees across supported destinations.

Yes. Premium+ provides full T.38 fax relay support, enabling reliable fax transmission over IP without quality degradation — essential for banking, legal, healthcare,

and government workflows that still rely on fax infrastructure. DTMF is supported via all three methods: RFC2833 (RTP Event),

in-band tone, and SIP INFO, ensuring compatibility with bank IVR systems, payment processing platforms, and enterprise PBX configurations that require reliable keypad signal pass-through.

For most MVNO deployments, Premium+ is the recommended and often architecturally required tier.

MVNOs need full end-to-end CLI transparency for subscriber compliance and number portability,

roaming signal support for CS (Circuit-Switched) roaming and VoLTE handoff, and guaranteed ASR to maintain subscriber experience quality standards.

The Premium+ Route’s direct Tier-1 interconnects provide all three. Operators building MVNO infrastructure on VoiceBuy should contact the technical sales team to discuss their specific core network architecture and roaming requirements.

The Premium+ Route targets up to 65% Answer Success Rate (ASR) with an Average Call Duration (ACD) of 5 to 10 minutes.

This is the highest ASR tier available on the VoiceBuy platform. Performance is backed by direct SLA agreements with Tier-1 carrier partners, meaning VoiceBuy does not rely on spot-market LCR pricing or secondary resellers that can introduce ASR variability.

For mission-critical deployments, contact the VoiceBuy technical team to discuss destination-specific ASR expectations and SLA documentation.

The Premium+ Route provides full CLI transparency,

T.38 fax support, and DTMF compatibility across 90% of global destinations. This includes major fixed-line and mobile networks across Europe, North America,

Asia-Pacific, Latin America, the Middle East, and Africa. Roaming signal support for MVNO subscribers is available on supported destination networks. A full destination coverage list with per-prefix availability is accessible via your account dashboard at my.voicebuy.com.

Both routes provide stable CLI delivery and high ASR, but they differ in interconnect depth and capability ceiling.

Premium uses quality-optimized carrier selection (up to 50% ASR, regional coverage) and is suitable for standard corporate and retail VoIP. Premium+ uses exclusive direct Tier-1 interconnects (up to 65% ASR,

90% global destination coverage) and adds T.38 fax relay, full roaming support, and extended codec options including Opus and iLBC. Premium+ is the appropriate choice whenever compliance, subscriber-grade quality, or mission-critical reliability is a non-negotiable requirement.

The Premium+ Route supports the widest codec range of any VoiceBuy tier: G.711 alaw and ulaw, G.729, G.722 HD voice, iLBC, and Opus — subject to Tier-1 carrier compatibility at the destination.

Signalling uses standard SIP (RFC3261) with full compatibility for Class 4 and Class 5 softswitches. DTMF is supported via RFC2833, in-band, and SIP INFO. T.38 is supported for fax relay.

Full MVNO roaming signalling including CS roaming and VoLTE handoff is available on supported networks.