Retell AI alternatives: pick one by what is actually wrong

Short answer: switch to Vapi if you want more control over providers. Switch to Bland AI if you want one flat price with no model bill. Pick Bolna for Hindi and Indian telephony, and ElevenLabs Agents if the voice has to be excellent. Before any of that, make sure the problem isn't the knowledge base. If it is, it will move to the new platform with you.

Prices and limits below come from each company's own pages, checked on 21 September 2026.

First: what is actually wrong?

Retell does a lot out of the box. It gives you one per-minute price, 20 concurrent calls included, telephony, chat agents, and a knowledge base that crawls a whole website and refreshes it every 24 hours. People usually leave for one of five reasons, and each one points to a different alternative.

What's wrong on Retell	Look at	Why
The bill is too high with a strong model	Vapi, Bolna	Pay providers at cost, or use a cheaper regional platform
You want to choose every provider yourself	Vapi, Pipecat, LiveKit Agents	Built around picking your own speech, model and voice
You want one flat price to quote clients	Bland AI	$0.12 to $0.14 a minute with the model included
Callers speak Hindi or regional languages	Bolna	10+ Indian languages, rupee pricing, Indian carriers
The voice isn't good enough	ElevenLabs Agents	Voice-first platform, 70+ languages
The agent gives wrong answers	Your knowledge base	See the last section before you migrate

If the cost is the problem: Vapi or Bolna

Retell's agent pricing runs from $0.07 to $0.31 a minute. Most of that range comes from the model: Retell's own infrastructure is $0.055 a minute, voices are $0.015 (ElevenLabs voices $0.040), and telephony is $0.015. Past ten knowledge bases, each one costs another $8 a month.

Vapi charges $0.05 a minute for hosting and passes each provider through at cost. On Vapi's own list of typical provider prices, a phone call comes to about $0.08 to $0.14 a minute. There is no knowledge base fee. Bolna is 6 cents a minute pay-as-you-go, and about 4.2 to 4.6 cents on its $300 and $500 pilot bundles.

If you want control: Vapi, Pipecat or LiveKit Agents

Vapi lets you choose the transcription, model, voice and phone carrier for each agent. The trade-off on the knowledge base: it takes uploaded files only (keep each under 300 KB), and your system prompt has to tell the agent when to use the query tool. The docs are blunt that the description alone is not enough.

Pipecat and LiveKit Agents go further. They are open-source frameworks, so you host the agent yourself, wire in any providers you like, and build retrieval however you want. You pay only the providers and your servers, and you maintain all of it.

If you want one price: Bland AI

Bland includes the model, transcription and voice in one per-minute rate: $0.14 on the free Start plan (100 calls a day, 10 at once) and $0.12 on Build ($299 a month, 2,000 calls a day, 50 at once). It is the easiest of these to quote to a client, and the daily caps matter if you run outbound campaigns.

If your callers speak Hindi: Bolna

Bolna lists 10+ Indian languages, including Hindi, Hinglish, Tamil and Telugu, and prices in both rupees and dollars. It connects to Twilio, Plivo and Vobiz, supports a knowledge base with RAG, and lets you bring your own model and voice keys. If you build AI calling agents for Indian businesses, it belongs on your shortlist whatever else you use.

If the voice is the problem: ElevenLabs Agents

ElevenLabs charges $0.08 a minute standard ($0.16 at burst), and every plan includes minutes, from 15 on the free tier to 3,738 on Business. It covers 70+ languages. One detail is worth knowing: a knowledge base document of up to roughly 300,000 characters can sit in the agent's full context instead of going through retrieval. For a small business, that removes the step where the wrong chunk gets picked.

If the agent gives wrong answers, don't migrate yet

Of all the reasons to leave, this is the one a new platform is least likely to fix.

Retell reads the knowledge base the way every platform does. It cuts the text into chunks, and on each turn it gives the model the closest few, three by default. If the client's fees page is a table of prices, one chunk can hold "$350" with no treatment name next to it. The agent then reads that out when someone asks about implants. Point Vapi, Bland or Bolna at the same text and you get the same wrong answer.

What fixes it is rewriting the source. Name the product in every sentence that has a price, time or size in it. List products by name only. Settle contradictions between pages before you load them. And write a sentence for every likely question, even if the answer is "not confirmed". How to write a chatbot knowledge base covers each step, and on Retell you can raise the chunk count (up to 10) while you test.

KB Builder does the rewriting for you. Give it a client's website and documents and it returns a knowledge base for whichever platform you land on, plus a list of what the website never says.

Once you've chosen: set up its knowledge base properly

Each platform stores and searches a knowledge base differently: what files it takes, how many pieces it hands the agent per turn, and whether the agent searches at all without being told. Our setup guides cover that from each platform's own documentation, with the prompt lines we add after our own live calls:

• Setting up the Vapi knowledge base
• Setting up the Bland AI knowledge base
• Setting up the Bolna knowledge base
• Setting up the ElevenLabs knowledge base

KB Builder is made by MasterBlocks, which also makes SpeakEdge, a voice agent platform. We left SpeakEdge off this list. We are not affiliated with any platform named here.