Top-rated Wholesale VoIP Termination Providers in the US

Key Factors to Consider Before Partnering

Selecting a wholesale SIP termination provider requires moving past marketing promises and analyzing cold, hard data. The difference between a profitable route and a revenue-draining complaint lies in these core performance indicators.

Quality Assurance: ASR, PDD, and Uptime (The Technical Core)

The reliability of a provider is measured by specific QoS (Quality of Service) metrics that determine call success and user experience.

• ASR (Answer Seizure Ratio): This is the percentage of successfully answered calls to the total number of attempted calls. Preferred Standard: Reputable US wholesale termination voip providers maintain an ASR well above 70%, often pushing into the 80−95% range for high-quality domestic routes.
• PDD (Post-Dial Delay): This is the time lapse from when the caller finishes dialing to when the ring-back tone begins. Preferred Standard: PDD should be under 5 seconds. If PDD exceeds 150ms, users perceive a delay, often resulting in them talking over one another.
• Network Uptime SLA: A service level agreement (SLA) on uptime should be mandatory. Our platform and other leaders in the market guarantee a 99.9%+ Uptime SLA, ensuring your service continuity is protected with financial penalties for failure.
• Latency: The delay in voice transmission. For optimal HD Voice Quality, Latency should be kept to an absolute minimum. Softtop focuses on ultra-low latency, averaging <25ms for US domestic routes by leveraging geo-redundant Points of Presence (PoPs).

Transparent Pricing Models: LCR vs. Premium Routes

The wholesale market offers two primary routing philosophies, each with a distinct impact on cost and quality. A top-rated provider offers both with clear distinction.

• Premium Routes: These routes use Tier 1 carriers and direct interconnections, ensuring the highest ASR and best Call Line Identification (CLI) delivery. business-critical calls where quality is paramount.
• LCR (Least Cost Routing): LCR dynamically selects the lowest-priced available route for every call. While this maximizes margin, LCR quality can be variable and should be reserved for less sensitive traffic, such as bulk notifications or secondary dialer campaigns.
• Billing: Look for transparency. Per-second billing is the industry standard for minimizing costs, as it prevents rounding up partial minutes, saving significant money on high volumes of short-duration calls.

Security and Technology: AI-Powered Fraud Protection

Fraud is a multi-billion dollar problem in the telecom industry. Your provider’s security is an extension of your own risk management.

• Real-Time AI Monitoring: The most effective defense uses AI and Machine Learning to establish a traffic baseline and instantly block anomalies, such as sudden spikes in high-cost international calls.
• CLI Spoofing & Robocalling: Fraudsters falsify the Caller ID (CLI Spoofing) to appear as a local number, damaging your brand’s reputation and leading to regulatory risk. Providers must implement STIR/SHAKEN compliance (mandatory for US traffic).
• Traffic Refilling: A type of fraud where a low-cost route is masked as a premium route. A good provider detects this fraud automatically to protect your revenue stream.

Compliance and Portability (E911 & Kari’s Law)

For any sip termination provider operating in the US, compliance is non-negotiable.

• E911 and Kari’s Law: Providers must ensure E911 services are enabled and comply with Kari’s Law and the RAY BAUM’s Act. This mandates that multi-line phone systems (MLTS) allow direct 911 dialing (no prefix needed) and transmit the caller’s dispatchable location to the Public Safety Answering Point (PSAP).
• Portability: The ability to seamlessly and quickly port in your existing numbers (Local and Toll-Free DIDs) is essential for business continuity.

Top Wholesale VoIP Termination Providers in the US

The market is fragmented, ranging from global Tier 1 carriers who own the fiber to developer platforms who specialize in API integration.

1. Softtop: Tier-1 Quality and Flexible Solutions

Softtop is positioned as a quality-focused partner that bridges the gap between ultra-premium (and expensive) Tier 1 carriers and purely cost-driven LCR platforms. Our infrastructure is engineered for maximum performance, making us the ideal choice for businesses where reputation and voice clarity are critical.

• Superior HD Voice Quality: We leverage strategically placed Points of Presence (PoPs) and Tier-1 interconnects to guarantee ultra-low latency, reflected in an average PDD below the industry’s preferred standard.
• AI Routing Intelligence: Our proprietary system goes beyond basic Least Cost Routing (LCR) by implementing AI Routing. This dynamically optimizes every call based on real-time quality metrics (not just static rates) to ensure the best balance of cost and performance.
• Advanced Fraud Shield: Our platform includes an integrated AI Fraud Protection system that monitors traffic in real-time, detecting and blocking threats like high-volume CLI spoofing and complex revenue-affecting traffic patterns.

2. Bandwidth: The North American Network Owner

Bandwidth is highly valued because it owns its core network infrastructure in North America, giving it unparalleled control over quality and regulatory compliance.

• Core Strength: Network ownership provides a single point of accountability for routing, latency, and E911 services.
• Compliance Leadership: They are known as a leader in providing the compliant infrastructure required by Kari’s Law and the RAY BAUM’s Act.
• Best For: Companies building Communication Platform as a Service (CPaaS) applications or large enterprises requiring a single, highly redundant North American provider.

3. Twilio: The Developer’s Choice for Programmable Voice

Twilio pioneered the developer-first approach to telecom. While they are a CPaaS platform first, their wholesale SIP termination offerings (Elastic SIP Trunking) are globally recognized.

• Core Strength: Their powerful APIs give developers granular control over every aspect of the call flow.
• Best For: SaaS businesses, tech companies, and platforms that need to embed voice capabilities directly into their application, CRM, or custom software. Their strength is programmability and speed to market.

4. Telnyx: Global A-Z Termination & Security

Telnyx operates its own private, global IP network backbone, which bypasses the public Internet for voice traffic, giving them strong control over quality and security.

• Core Strength: Focus on global A-Z termination routes and robust encryption protocols, including TLS/SRTP, to secure signaling and media.
• Best For: International carriers and companies requiring high-security, encrypted voice communications across multiple continents.

5. Other Notable US Providers

• VoIP.ms: A flexible, feature-rich provider that operates on a pay-as-you-go model. Best for small resellers and businesses requiring a vast array of included features and competitive LCR pricing.
• Tata Communications: Leveraging one of the world’s largest Tier-1 IP networks, Tata is a classic powerhouse, best suited for multinational corporations and very large carriers needing enterprise-grade stability and vast global reach.
• IDT Express: Known for offering aggressive rates, particularly into difficult-to-reach emerging markets. A popular choice for resellers focused purely on cost optimization and volume.