PolyAI has become a go-to name for enterprise-grade voice assistants, prized for lifelike conversations, robust contact-center integrations, and global language coverage. Within the broader conversational ai landscape, PolyAI stands out as a leading solution, but there are many poly ai alternatives that offer different features, scalability, and pricing models for businesses of all sizes.
If you’re running large volumes and care about brand-safe, natural voice at scale, it’s easy to see the appeal. Still, many teams now evaluate options that move faster to value, expose more self-serve controls, or offer simpler, usage-based pricing.
In this article, we’ll unpack what PolyAI does well and help you find the best poly ai alternative for your needs, depending on your goals around speed, transparency, and developer control.
PolyAI is a conversational AI platform that builds customer-led voice assistants for enterprises, capable of fielding and resolving complex calls across industries like banking, hospitality, insurance, retail, and telecom.
Their platform leverages advanced AI models and natural language processing to deliver lifelike, human-like conversations. PolyAI's natural language understanding capabilities enable it to interpret and respond to complex customer inquiries. The platform emphasizes natural, interruption-friendly conversations (“barge-in”), multilingual support (45+ languages), and contact-center use cases such as authentication, billing, bookings, and payments.
On the trust side, PolyAI highlights SOC 2 Type II and ISO 27001, plus a per-minute pricing model that includes ongoing improvements, maintenance, 24/7 support, and a 99.9% phone-line SLA.
Even with strong conversational quality and enterprise guardrails, buyers often explore alternatives when they need a different trade-off profile:
Teams may also seek alternatives with enhanced ai capabilities tailored to their specific requirements.
Retell is one of the top alternatives to Vapi, and is considered among the leading conversational ai platforms for building AI voice agents. This section will compare leading conversational ai platforms, each with unique strengths. Exploring these options can help you find the best fit for your needs, whether you prioritize advanced features, performance, or the cheapest solution for specific use cases.
Retell offers a developer-friendly platform with a drag-and-drop interface for quickly building, deploying, and monitoring AI voice agents. It supports advanced LLMs, multilingual voice models, real-time workflows, and integrations with telephony providers like Twilio. Some platforms, including Retell, offer industry specific solutions tailored to sectors like healthcare, finance, or retail.
These features can help expand your reach by supporting multiple languages and broader user engagement across various communication channels.
For a clear overview, see the table below summarizing key features and use cases of each alternative, including cost-effective options and their benefits. Retell also includes pre-built templates for common use cases like lead qualification, appointment booking, and customer support. These platforms are designed to enhance customer engagement across multiple communication channels.
Retell AI excels in areas like low-code infrastructure, rapid deployment, and easy integration, making it stand out for teams looking to quickly implement voice AI solutions.
Here’s a breakdown of Retell’s pricing. Retell is among the cheapest options for enterprise-grade voice AI. Pay-as-you-go starts at $0.07+ per minute, with volume discounts down to $0.05/min for enterprise plans. For organizations with unique requirements, custom pricing is available to ensure flexibility and tailored solutions beyond standard tiers. You are charged only for connected calls, not for idle time. The base price covers core voice AI services, while the rest of the costs include telephony and advanced large language models. Free $10 credit and limited concurrent calls are included for testing.
Number rental is only $2 per month, and toll-free numbers are only $5 per month.
G2 Rating: 4.8/5 (612 reviews)
Review: “Retell AI has completely transformed the way we manage automated calls, with impressive voice quality and understanding”.
Product teams and enterprises seeking a scalable, flexible voice AI platform that can be tailored to specific business needs, with transparent pricing, especially those focused on call centers and outbound sales automation, will find Retell a strong choice. Retell is also suitable for smaller businesses and small businesses seeking scalable solutions. The platform supports ai powered call centers and ai powered voice agents for efficient, human-like customer service.
Synthflow is a scalable voice AI with a no-code visual workflow builder, real-time personalization, and deep CRM integrations. Supports HIPAA compliance, inbound routing, and multi-tenant management for agencies. Designed for production-grade voice automation.
These features contribute to higher customer satisfaction.
Here’s a breakdown of Synthflow’s pricing:
The starter plan is one of the cheapest options for entry-level users, starting at $29/month for 5,000 minutes and 1 agent. The Growth plan at $99/month includes 20,000 minutes and unlimited agents. The Scale plan at $249/month supports 60,000 minutes. For large-scale deployments, custom pricing is also available to accommodate unique enterprise needs.
G2 Rating: 4.5/5 (815 reviews)
Review: “What I like best about Synthflow is that it doesn’t bury you in technical complexity. You don’t need to be a coder or spend weeks wiring together APIs just to get a usable AI voice agent”.
Marketing teams and enterprises with specific business needs in compliance and automation, as well as those requiring robust inbound support automation and deep integrations. E commerce businesses seeking advanced automation will also find Synthflow a strong choice, as it offers tools for customer sentiment and customer sentiment analysis to improve service quality.
Synthflow is a scalable voice AI with a no-code visual workflow builder, real-time personalization, and deep CRM integrations. Supports HIPAA compliance, inbound routing, and multi-tenant management for agencies. Designed for production-grade voice automation.
Replicant is an enterprise-grade automation platform for contact centers.
Its “Thinking Machine” resolves Tier-1 customer calls autonomously, escalates to live agents when needed, and integrates with backend systems to complete workflows. The platform includes analytics and conversation intelligence tools for optimizing performance at scale.
Replicant does not publish pricing publicly. Engagements are structured as enterprise contracts, tailored to call volumes and complexity.
G2 Rating: 4.7/5 (45 reviews)
Review: "The team is quick to reply if there are any technical concerns and is open to feedback. They usually respond within an hour when a ticket is sent in".
Large-scale contact centers that want to automate high call volumes end-to-end, with the support of an established vendor in the voice automation space.
Bland emphasizes hyper-realistic voice experiences with strong security and data governance. It supports high-volume inbound and outbound calling, SMS, and omnichannel workflows. Bland markets itself as capable of scaling up to one million concurrent calls, making it attractive to enterprises that demand resiliency.
Bland's unified approach helps engage customers across all channels, improving customer engagement and satisfaction.
No public pricing. Bland generally positions itself at the enterprise tier, with costs reflecting its scale and customization focus.
Product Hunt Rating: 3/5 (10 reviews)
Large enterprises with strict requirements for privacy, governance, and brand voice customization at scale.
Cognigy is a conversational automation platform built for complex, enterprise-grade deployments.
It supports voice and chat channels, advanced orchestration, multilingual interactions, and customizable workflows, making it a flexible option for multinational organizations.
Cognigy leverages generative ai and advanced natural language processing to deliver more human-like interactions, better context understanding, and improved customer support.
Enterprise licensing, typically customized to deployment scale and channel usage. Custom pricing is available based on deployment scale and requirements. Pricing is not publicly listed.
G2 Rating: 4.6/5 (13 reviews)
Review: “Overall I loved it but I must mention that it does not support an extensive workflow”.
Global enterprises with complex workflows, multiple channels, and a need for deep orchestration across languages and regions.
Kore.ai provides a platform for building intelligent virtual assistants across voice, chat, email, and social media.
Its low-code design tools, built-in NLP, and analytics capabilities make it a versatile option for teams that want to reduce engineering lift while maintaining enterprise-grade functionality.
Kore.ai offers tiered plans (e.g. Essential, Advanced, Enterprise), where only the top tier is custom-priced. For large deployments, custom pricing is available to accommodate unique business requirements.
They also charge for model compute via “model credits” as part of infrastructure usage. For large deployments, especially in voice or agentic AI, pricing is negotiated case by case, with usage, concurrency, channel mix, and features all influencing the final quote.
G2 Rating: 4.3/5 (12 reviews)
Review: “User friendly, fast and many supported languages. Very complex setup process and more bugs then competitors”.
Organizations that need a balanced multichannel solution with lower setup overhead and strong low-code capabilities.
Sierra AI deploys advanced AI agents for customer service that are uniquely trained to align with a company's specific brand identity.
These agents can reason, predict, and take action not just based on a knowledge base, but also by adhering to the company’s tone, values, and policies for a highly personalized interaction.
Sierra offers a strong balance between automation and human support, with AI designed to manage many tasks that could potentially ai replace those traditionally handled by human agents, while still allowing for escalation to human staff when necessary.
G2 Rating: 4.3/5 (12 reviews)
Review: “User friendly, fast and many supported languages. Very complex setup process and more bugs then competitors”.
Sierra’s pricing begins at approximately $150,000 annually, making it a more cost-effective alternative for sophisticated AI.
Final pricing is custom pricing, determined based on agent complexity and expected interaction volume. This structure provides a lower total cost of ownership compared to Kore.ai while delivering powerful, brand-aligned automation.
Customer-centric brands where a consistent voice and adherence to company policy are critical, especially in telecommunications and financial services managing diverse customer segments.
Voiceflow is a leading no-code platform for designing conversational workflows across both voice and chat.
It excels in prototyping and collaboration, allowing teams to co-design flows, manage knowledge bases, and test experiences before launch.
Voiceflow offers a free plan for basic usage. The Pro plan starts at $60 per editor/month for up to 20 agents, while the Business plan at $150 per editor/month supports unlimited agents. Enterprise pricing is available on request.
G2 Rating: 4.6/5 (58 reviews)
Review: "Good platform if you have less than 5,000 chats per month, otherwise extremely expensive".
Startups, design teams, and innovators building prototypes or multichannel bots where iteration speed is more important than call concurrency.
Ada.cx powers AI agents that automate customer service across chat, voice, and email, helping support teams handle complex requests at scale.
Unlike traditional bots that rely on rigid scripts, Ada’s platform was built “AI-first”, meaning its agents can understand intent, trigger workflows, and even escalate to humans when needed, all while maintaining a consistent brand tone.
G2 Rating: 4.6/5 (155 reviews)
Review: “Ada helped our small support team contain the most easy-to-resolve customer inquiries, freeing-up more time for agents to go through our backlog.”
Ada uses a performance-based pricing model, where companies pay based on successful resolutions or interaction volume rather than flat usage fees. Exact pricing depends on the number of monthly conversations, integrations, and deployment channels, but most enterprise plans start in the low six figures annually. For organizations with unique requirements, custom pricing is available based on conversation volume and integrations.
Brands that prioritize customer experience at scale, especially e-commerce, fintech, and telecom companies, where multilingual support and fast automation setup are key.
Decagon.ai offers a unified AI engine that auto-resolves customer issues across chat, voice, email, SMS, and custom channels in any language.
Their approach centers on Agent Operating Procedures (AOPs): natural-language instructions that compile into logic, allowing teams to tweak behavior without heavy coding.
Decagon frames pricing around value. Their two main tiers are:
Because Decagon is aimed at enterprise clients with large volumes, their base pricing is custom. Custom pricing is determined based on volume and complexity, allowing for tailored solutions that meet unique business needs. In one public review, estimated ranges span $95,000 to $590,900+ per year, depending on complexity, volume, and integrations.
G2 Rating: 4.9/5 (18 reviews)
Review: “The biggest upside of using Decagon isn’t simply the assumption of repetitive day-to-day tasks that would normally be done manually, but that Decagon allows us to evaluate data on a much deeper level.”
Organizations that demand high customization, transparency, and outcome-driven automation, especially in sectors like fintech, telecom, or SaaS with large support loads.
ElevenLabs is best known for its world-class text-to-speech and voice cloning tech, and more recently it’s expanded into conversational AI agents. Their platform can take user input (voice or text), ground it in your data, and produce natural spoken replies.
It’s not yet a full-blown telephony agent system, but it bridges content and voice interaction nicely, especially for brands already working in audio, narration, or voice experiences.
ElevenLabs uses a credit system. You get a bundle of credits (usable for TTS, agents, etc.), and if you exceed them, you buy more.
Example tiers (as of now):
Because it’s usage-based, your total cost will depend heavily on how many agent minutes you use, how much audio you generate, and how premium the voices are.
If your product or brand already has a voice or audio focus (podcasts, narration, gaming, or voice apps) and you want to layer in conversational agents, ElevenLabs is a powerful pick. It’s especially strong when you care deeply about sound quality, expressiveness, and voice branding. But if your priority is full telephony integration, call switching, deep voice workflows, or super predictable pricing, PolyAI (or others) might still lead in those domains.
PolyAI is still one of the most impressive players in the enterprise voice AI space. Its lifelike conversations, multilingual coverage, and strong reliability make it an obvious choice for large organizations. But as we’ve seen across multiple deployments, that same enterprise focus can make things slower, pricier, and harder to iterate when your team needs to move fast.
That’s exactly why Retell AI stands out. It’s purpose-built for real-time voice automation with sub-second latency, a no-code builder that anyone can use, and transparent, pay-as-you-go pricing. Retell gives you full control over customization, LLM choice, and telephony integrations, without sacrificing speed or compliance.
From my experience comparing dozens of platforms, Retell consistently delivers the best mix of performance, flexibility, and clarity. While tools like Synthflow, Cognigy, or Kore.ai shine in their own niches, Retell hits the sweet spot: fast enough for startups, robust enough for enterprises, and simple enough for teams that just want to build, test, and launch without friction.
If I had to choose one platform to recommend as the next step beyond PolyAI, Retell AI would be it — the voice platform that actually keeps up with how modern teams build and scale in 2025.
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