Certified Elite Retell Partner

Highest tier certification · Official Partner Network

We Build the Hardest Retell Integrations.

Call Sandwich is a certified Elite-tier Retell AI partner — the highest level in Retell's partner program. We integrate Retell's voice AI agents into enterprise telephony systems that standard agencies won't touch.

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SIP trunk integration White label capable Any telephony stack Production ready

Partnership Tier

Elite Partner

Official Retell AI Partner Network · Highest certification

Advanced telephony integration expertise
Enterprise SIP/WebRTC deployment capability
Production-grade multi-tenant builds
Dedicated integration engineering team
White-label platform development
Retell + legacy system bridging (ViciDial, Asterisk)
Real-time CRM sync during active calls

Elite

Tier

15+

Platforms

∞

Scale

What We Build

Retell AI Solutions for Every Enterprise Use Case

From outbound AI sales agents to enterprise inbound routing — we've built it on Retell.

📤

Outbound AI Sales & Lead Gen

Deploy Retell AI agents that call thousands of leads simultaneously, qualify prospects, and transfer hot leads live to your sales team. Integrated directly with ViciDial or any predictive dialer.

📥

Enterprise Inbound Routing

Replace your IVR with a conversational Retell AI agent. Integrate with NICE, Avaya, or Genesys to route calls intelligently, handle overflow, and provide 24/7 first-contact resolution.

🔄

AI + Human Handoff

Build seamless warm transfer flows where Retell AI agents collect context and hand off to live agents with full transcript and CRM data pre-populated. Zero friction, zero dead air.

📅

Appointment Setting

AI agents that call leads, qualify them, and book appointments directly into your calendar (Calendly, GHL, custom). Integrate with your CRM for real-time disposition updates.

💳

Debt Collection & Payment

PCI-compliant Retell AI agents for outbound debt collection. Negotiate payment plans, take payments via DTMF, and update your debt management software in real time.

🏷️

White-Label Platforms

Need to resell voice AI under your brand? We build fully white-labeled Retell-powered platforms with multi-tenant agent management, billing integration, and client dashboards.

The Process

How We Deploy Retell in Your Stack

A repeatable, low-risk process refined across dozens of enterprise Retell deployments.

Telephony Stack Audit

We map your existing telephony infrastructure — SIP trunks, PBX, CCaaS platform, dialers, carriers. We identify the optimal integration point for Retell AI and define the architecture.

Voice AI Architecture Design

We design the conversation flows, define agent personas, engineer prompts for your specific use case, and plan the integration layer between Retell and your telephony system.

Build & Integration

Our engineers configure the SIP trunk connections, build the call routing logic, implement CRM webhooks, and deploy the Retell agents to your production environment with staging validation.

QA & Load Testing

We run comprehensive QA — from conversation flow testing to 100+ concurrent call load tests. We optimize latency, fine-tune the AI behavior, and ensure enterprise-grade reliability.

Go Live & Ongoing Optimization

Controlled rollout with real-time monitoring. Post-launch, we analyze call recordings, iterate on prompts, and continuously improve performance as your AI agent scales.

Retell + Your Stack

We Connect Retell to Everything

If it has a SIP trunk, webhook, or API — we can connect it to Retell.

ViciDial

Legacy Dialer

Asterisk

Open Source PBX

FreeSWITCH

Soft Switch

NICE inContact

Enterprise CCaaS

Avaya

Enterprise PBX

Talkdesk

Cloud CCaaS

Genesys

Cloud CCaaS

NetSapiens

UCaaS Platform

Twilio

Cloud CPaaS

Telnyx

CPaaS

382 Communications

CPaaS

Salesforce

CRM

HubSpot

CRM

GoHighLevel

CRM / Marketing

Zoho CRM

CRM