Retell AI vs Vapi AI: 2026 AI Voice Agent Comparison

Retell AI and Vapi are two popular choices for building AI voice agents, but deciding between them isn’t as simple as comparing their features or per-minute pricing.

Both platforms can handle inbound and outbound calls, qualify leads, book appointments, and automate customer support. The differences become clearer when you look at how much technical work each requires, how much control you have over the underlying AI models, and what happens when call volumes increase.

Retell AI focuses on making voice automation accessible to businesses, while Vapi offers greater customization for developers. Neither approach is automatically better, and the actual costs depend heavily on your configuration.

In this Retell AI vs Vapi comparison, we’ll examine their features, voice quality, integrations, pricing, and limitations to help you decide which platform fits your needs.

TL;DR

Get the better alternative to Retell and Vapi for voice AI. Book a demo with Quiq today.

Retell AI and Vapi at a glance

Retell AI and Vapi are two platforms for building AI voice agents that handle inbound and outbound calls, automate customer support, and connect with business systems. Both launched in 2023, although Retell became publicly available in early 2024.

Retell AI was founded in San Francisco in 2023 by Bing Wu and four cofounders. The company joined Y Combinator’s Winter 2024 batch and initially focused on helping businesses automate phone conversations. Since then, Retell has expanded into a broader customer experience platform.

Its primary audience includes contact centers, sales teams, and businesses that want to deploy voice agents without extensive development work. Retell offers a visual agent builder, built-in telephony, call routing, and conversation analytics, alongside APIs for custom integrations. This can be too much for smaller businesses that often look at Retell alternatives instead.

Vapi emerged in 2023 when founders Jordan Dearsley and Nikhil Gupta pivoted from their productivity startup, Superpowered. Also based in San Francisco, Vapi was originally designed for developers building custom voice applications.

The platform gives businesses considerable control over voice providers, language models, transcription services, and conversation logic. Vapi has since added visual workflows and natural language agent configuration, making it more accessible to users without coding experience.

The biggest differences between Retell AI and Vapi concern customization, deployment, and pricing.

Retell prioritizes ready-to-use calling features and centralized agent management. Vapi offers more freedom to configure the underlying technology, although advanced deployments can need more technical involvement.

Their billing approaches also differ. Retell itemizes voice infrastructure and model costs within its usage rates, while Vapi charges a platform fee alongside third-party provider costs.

Retell AI vs Vapi: Key features compared

Retell AI and Vapi share many basic features, including inbound and outbound calling, conversational AI, and integrations with external applications. However, their approaches to building voice agents, configuring models, and managing production deployments are different.

Let’s examine the key differences in this feature comparison, including where each platform has an advantage.

Voice AI agents and call automation

Both Retell AI and Vapi can automate common phone interactions, including customer support, lead qualification, appointment scheduling, and sales calls.

Retell AI offers a complete calling environment where businesses can build AI agents, connect phone numbers, and manage conversations from a central dashboard.

Agents can access customer information, answer questions from a knowledge base, book appointments, and transfer conversations to employees.

One of Retell’s more practical features is batch calling, which lets you run outbound campaigns by uploading a CSV file containing customer phone numbers and other information.

You can schedule campaigns, personalize calls with customer details, and monitor your results. Retell also lets you reserve call capacity for incoming calls so that outbound campaigns don’t occupy every available line.

Vapi supports similar automation, including batch calling through its outbound campaigns functionality. Users can upload up to 10,000 contacts per campaign, configure calling windows, and control concurrent calls.

However, Vapi has a really interesting feature called Squads.

Squads allow several specialized AI agents to handle different stages of a conversation. For example, one agent could qualify a lead, another could answer product questions, and a third could handle appointment booking.

Retell also supports structured conversations and transfers between agents, so complex interactions are possible on either platform.

For companies primarily interested in managing phone operations, Retell’s campaign and calling tools are particularly accessible. Vapi offers more flexibility for developers building custom automation around individual calls.

Ease of use and agent setup

Retell AI has an advantage for non-technical users who want to create and manage voice agents without writing code.

The platform offers a visual Conversation Flow builder that lets users organize conversations into individual nodes, configure conditional transitions, and connect actions.

You can also build an agent using a single prompt that explains how it should behave.

Retell recommends starting with a single prompt and moving to Conversation Flow when more control is necessary.

Another feature is Conductor, an assistant that helps users configure and test agents through natural language instructions.

Vapi has made progress in making agent creation more accessible, but its approach is still more developer-oriented.

Users can create basic agents from the dashboard, select predefined model configurations, and use Composer to generate agent configurations from written instructions.

However, Vapi retired its previous Workflows builder in August 2026. For more complex conversations, the platform now recommends Assistants and Squads.

This means developers typically need to configure specialized assistants and define how conversations move between them.

Retell is generally easier for business users who want a visual, low-code approach to building voice agents.

Vapi is more appropriate for technical teams comfortable configuring APIs, managing model settings, and testing custom applications.

Of course, creating an initial agent is considerably easier than preparing one for a production deployment. Both platforms still require testing, careful conversation design, and ongoing adjustments.

Voice quality, latency, and conversational accuracy

Voice quality is difficult to compare without testing both platforms under identical conditions.

Retell AI uses its own conversational orchestration technology, with support for different language models and voice providers.

Users can configure interruption sensitivity, speaking speed, pauses, and how the agent responds when customers stop talking.

Retell also supports voice cloning and multilingual conversations.

The company advertises approximately 600ms latency, although actual response times depend on the model, voice provider, and complexity of the conversation.

Vapi also prioritizes low latency, but gives users more control over the technologies involved in generating responses.

Its voice processing pipeline includes:

• Speech-to-text: Converts spoken language into text using providers such as Deepgram or Gladia.
• Language model: Processes the conversation using models from OpenAI, Anthropic, Google, or other providers.
• Text-to-speech: Generates spoken responses using providers such as ElevenLabs, Cartesia, or Deepgram.

Vapi allows developers to configure these components independently and experiment with multiple providers.

This flexibility is useful when a business needs specific languages, voices, or performance characteristics.

However, additional configuration doesn’t automatically produce better conversations.

Poorly written prompts, slow API responses, and inaccurate transcription can affect either platform.

Retell offers a more managed voice experience with configurable options. Vapi gives developers greater freedom to optimize individual components.

Neither platform can guarantee consistently superior voice quality without testing the actual use case.

Customization and API capabilities

The biggest technical difference in the Vapi vs Retell comparison concerns how much control developers have over the underlying voice infrastructure.

Vapi was designed around developer APIs.

It lets businesses configure transcription engines, language models, and voice providers independently. Developers can also connect custom models, build tools, and manage agents programmatically using SDKs and APIs.

For instance, a company could use a custom speech recognition provider, send conversation data to a proprietary language model, and generate responses with ElevenLabs.

Vapi also supports versioning, configuration management, and automated testing through development pipelines.

Retell provides APIs and customization options too.

Developers can create agents programmatically, connect custom language models through WebSockets, configure external functions, and modify conversation behavior.

Its Conversation Flow builder is particularly useful for workflows requiring more control over the order of operations.

For example, a professional services company could configure an agent to verify customer information before discussing account details or scheduling appointments.

Retell’s newer Workflows functionality also allows businesses to retrieve information before calls and update connected systems afterward.

However, Vapi generally offers more freedom to replace individual parts of the speech processing system.

Vapi is the better choice if technical flexibility is your priority. Retell is easier to manage when the business wants to configure sophisticated conversations without maintaining every underlying component.

Integrations, knowledge bases, and multiple channels

Both platforms can connect voice agents to business applications, although the available integrations and setup requirements differ.

Retell supports integrations with Salesforce, HubSpot, Zendesk, GoHighLevel, Cal.com, and other services.

In October 2026, Retell introduced Workflows, which can retrieve CRM or helpdesk information before a call and update records after the conversation ends.

For example, an agent can retrieve an existing support ticket, discuss the problem with the customer, and update the ticket afterward.

Retell also supports website chat and SMS alongside voice calling, which is useful for businesses that communicate with customers across multiple channels.

Its knowledge base functionality accepts documents, website URLs, and text content. It can also synchronize information from Google Drive, OneDrive, and Notion.

Vapi supports integrations through APIs, webhooks, MCP tools, and connections to services such as Make, n8n, and GoHighLevel.

Developers can build custom actions that retrieve customer records, update CRM information, or interact with internal business applications.

Vapi also supports knowledge bases, which agents can query during conversations. However, its built-in retrieval functionality currently has more restrictive provider requirements than Retell’s.

Vapi supports voice interactions through phone calls and embedded web applications. Other communication channels can be connected through external services.

Retell offers more directly accessible business integrations and knowledge management options.

Vapi gives developers more control over integrations, although connecting several applications may require additional development work.

Call routing, transfers, and human handoffs

Both Retell AI and Vapi support call transfers, including warm transfers that provide human agents with context before connecting customers.

Retell offers several transfer options, including:

• Cold transfers that connect customers directly to another number.
• Warm transfers that introduce the customer or summarize the conversation before connecting.
• Agentic warm transfers where another AI agent contacts the receiving employee and confirms availability.
• Dynamic call routing based on information collected during the conversation.

Retell also supports live call monitoring, allowing supervisors to observe conversations and intervene when necessary.

Vapi offers comparable functionality through its Transfer Call tool.

Developers can configure transfer destinations, use conversation summaries, and define fallback behavior when a transfer fails.

The platform also supports assistant-based warm transfers, where a separate agent contacts the receiving employee before completing the handoff.

However, there are technical restrictions.

Some traditional Vapi warm transfer modes work only with Twilio. Assistant-based transfers support additional configurations, including Vapi phone numbers and compatible SIP connections.

Retell also depends on telephony configuration for certain transfer behaviors.

In practice, both platforms can handle more than basic call forwarding.

Retell has an advantage for contact center teams that want call routing and supervisor controls accessible through the same platform.

Vapi is more flexible for engineering teams that need to connect transfers to custom phone systems or build specialized routing logic.

Analytics, testing, and performance monitoring

Retell and Vapi both offer tools to monitor agent performance, investigate failed conversations, and test changes before deploying them.

However, the way they approach quality management is different.

Retell includes call recordings, transcripts, post-call analysis, and configurable analytics dashboards.

Businesses can track call volume, conversation outcomes, successful transfers, and other operational metrics.

Retell also offers simulation testing, agent version comparisons, and AI Quality Assurance tools that can evaluate conversations against predefined criteria.

There’s also live monitoring, allowing supervisors to observe conversations while they’re happening.

Vapi offers detailed technical monitoring alongside traditional conversation analytics.

Some of its key features include:

• Evals: Test specific agent decisions, responses, and tool calls using simulated conversation inputs.
• Simulations: Test complete conversations and identify problems before deployment.
• Monitoring: Track performance metrics and trigger alerts when configured thresholds are exceeded.
• Technical logs: Review API calls, transcription events, latency, and other information that helps developers diagnose problems.

These capabilities are particularly useful when several external providers are involved in a conversation.

For example, developers can investigate whether a delayed response originated from transcription, language model processing, or another component.

Retell offers accessible analytics and quality management features for contact center operations.

Vapi gives developers detailed visibility into application behavior and more control over automated monitoring.

Both require teams to define useful success metrics. A completed call isn’t necessarily a successfully resolved customer request.

Security and compliance

Security should be part of the evaluation for any business handling customer information over the phone.

Both Retell AI and Vapi offer security controls and support for regulated use cases, including healthcare.

Retell advertises SOC 2 Type II and HIPAA compliance, with support for Business Associate Agreements and controls for managing sensitive information.

The platform also offers features such as access controls, configurable data retention, and tools for protecting customer information.

Vapi is SOC 2 Type II attested and offers HIPAA compliance through a paid add-on.

However, enabling HIPAA mode places restrictions on which language models, voice providers, and transcription services can be used.

Vapi also supports custom storage configurations and data retention controls, which may be useful for enterprises with specific information security requirements.

Neither platform automatically makes every deployment compliant.

Businesses still need to review how recordings are stored, what information is shared with external providers, and whether callers must consent to recording or automated outreach.

This is particularly important for outbound sales calls, where telemarketing regulations may restrict how and when AI agents can contact customers.

Retell offers an accessible compliance setup for businesses that prefer a managed platform. Vapi offers extensive configuration options, but organizations need to assess security requirements across every connected provider.

The right platform depends on the company’s internal security policies, industry regulations, and deployment requirements.

Retell AI vs Vapi: Pricing comparison

Both Retell AI and Vapi use consumption-based pricing, so businesses pay according to their usage rather than committing to a large annual contract.

However, Retell bundles more of the voice infrastructure into its published rates, while Vapi charges a separate platform fee and passes through the costs of external providers.

Here’s how their pricing compares.

Retell AI pricing

Retell AI’s pricing starts at $0.07 per minute and can reach $0.31 per minute for standard voice configurations, depending on the language model and voice provider selected. Some premium configurations can exceed this range.

There are no mandatory subscription fees, and new customers receive $10 in credits to test the platform.

Retell breaks down voice AI costs into several components:

• Voice infrastructure: $0.055 per minute.
• Text-to-speech: Starts at $0.015 per minute, with higher rates for certain premium voices.
• Language models: Varies according to the selected model.
• Telephony: $0.015 per minute for supported US calling, with no additional Retell telephony charge for custom SIP connections.
• Additional features: Knowledge base access costs $0.005 per minute, while batch calling costs $0.005 per dial.

For example, an agent using GPT 5.1, Retell’s standard voice, and Retell telephony would cost approximately $0.125 per minute before optional features.

That works out to $125 for 1,000 minutes of customer interactions.

Retell also offers custom enterprise pricing for businesses with high call volumes, including volume discounts, higher concurrency limits, and optional dedicated implementation support.

The biggest advantage for non-technical teams is that they can manage most of the voice agent configuration and billing through a single platform.

Vapi pricing

Vapi’s pricing starts at $0.05 per minute for platform hosting. However, this doesn’t include the real costs of running the AI agent.

Businesses also pay for speech recognition, language model usage, and their selected voice model. Telephony charges may apply depending on the provider.

For example, Vapi estimates that 1,000 minutes using Deepgram, OpenAI, and ElevenLabs would cost approximately $82 to $129, without a paid support package or additional telephony fees.

Vapi also offers optional monthly subscriptions:

• Usage only: No subscription fee, with four concurrent calls and $5 in starting credits.
• Core ($29/month): Includes 10 concurrent calls, five phone numbers, and email support with a two-business-day response commitment.
• Pro (from $999/month): Includes 30 concurrent calls, dedicated Slack support, advanced access controls, and a 99% uptime SLA. Pricing is 10% of hosting fees, subject to the monthly minimum.
• Premier (custom pricing): Offers higher capacity, dedicated support, and enterprise infrastructure options.

These subscriptions are charged in addition to usage fees.

Vapi also charges $2,000 per month for its HIPAA compliance add-on.

Although Vapi passes through model costs without a markup, using multiple vendors can make billing and troubleshooting more complicated.

Which platform offers better value for money?

Retell AI is generally easier to budget for if you want a managed voice platform with fewer separate billing components. Its 20 included concurrent calls also give businesses more initial calling capacity than Vapi’s free allocation.

Vapi may be more economical for technical teams that can select inexpensive models and optimize their voice processing infrastructure. However, development and maintenance expenses need to be included in the calculation.

For larger deployments, Retell offers negotiated volume discounts, while Vapi has custom enterprise packages.

Neither platform is consistently cheaper across every configuration. The better choice depends on monthly call volume, voice quality requirements, selected models, and how much internal engineering work the business can handle.

Get the better alternative for enterprise voice AI agents

Retell AI and Vapi are capable platforms for automating phone conversations. Retell prioritizes easy setup and call management, while Vapi gives developers more control over voice engines and AI models. For service businesses focused exclusively on phone automation, either could be the right voice AI platform.

But enterprise customer service often extends beyond a single phone call. That’s where Quiq offers a significant advantage.

Quiq is a complete AI for CX platform: AI agents, AI assistants, AI services, conversation analysts, and human agents working together across voice, SMS, web chat, WhatsApp, Apple Messages, and RCS.

Customers can switch channels or reach a human agent without explaining their problem again. Our real-time conversational AI connects voice, SMS, web chat, WhatsApp, and human agents, maintaining context throughout the customer journey. Customers can switch channels or speak with an employee without explaining their problems all over again.

We also offer capabilities designed for complex enterprise customer service:

• Verified Intelligence: Independently verify agent actions, enforce guardrails, and see how decisions are made.
• Automated issue resolution: Use deep integrations with CRM and business systems to process returns, update accounts, and complete customer requests.
• Continuous quality monitoring: Analyze 100% of AI and human conversations to measure performance, identify problems, and improve customer experiences.
• Dedicated implementation support: Our team helps configure agents around your business processes, while AI Assistants support employees during customer conversations.

If you’re looking beyond basic voice automation and want AI agents that can resolve customer issues across multiple channels, book a demo to see what Quiq can do for your business.