AI chatbot pricing ranges from free to $500+/month depending on message volume and features. Most platforms charge per message or per credit, with hidden costs for branding removal and premium models. We compared 10 platforms so you can see what you'll actually pay.
How do chatbot platforms charge?
There are three main pricing models, and understanding the differences saves you from surprise bills:
- Per-message pricing — you pay for each message the chatbot sends. Simple to understand, but costs scale linearly with traffic. Used by Chatbase, Chatling, and SiteGPT.
- Per-credit pricing — messages cost different amounts depending on the LLM model used. A GPT-4 response might cost 10 credits while GPT-3.5 costs 1 credit. Used by CustomGPT and DocsBot. This model is confusing by design — it obscures the real per-message cost.
- Flat-rate pricing — you pay a fixed monthly fee for a set number of messages with no per-message variance. Used by rentabot.chat and some Tidio plans. Easiest to budget for.
Complete pricing comparison
| Platform | Free Tier | Entry Plan | Mid Plan | High Plan | Billing Model |
|---|---|---|---|---|---|
| Chatbase | 100 msgs/mo | $19/mo (2K msgs) | $99/mo (10K msgs) | $399/mo (40K msgs) | Per-message |
| Chatling | 35 msgs/mo | $15/mo (500 msgs) | $59/mo (5K msgs) | $249/mo (unlimited) | Per-message |
| Botsonic | 100 msgs/mo | $49/mo (3K msgs) | $149/mo (12K msgs) | $499/mo (50K msgs) | Per-message |
| SiteGPT | None | $49/mo (500 msgs) | $99/mo (2K msgs) | $399/mo (10K msgs) | Per-message |
| CustomGPT | None | $89/mo (1K credits) | $449/mo (5K credits) | Custom | Per-credit |
| DocsBot | None | $19/mo (1K msgs) | $49/mo (5K msgs) | $199/mo (25K msgs) | Per-credit |
| Tidio | 50 convos/mo | $29/mo (100 convos) | $59/mo (500 convos) | $159/mo (2K convos) | Per-conversation |
| Botpress | 5 bots, limits | $49/mo (2K msgs) | $149/mo (10K msgs) | Custom | Per-message + add-ons |
| Voiceflow | Sandbox | $50/mo (1K interactions) | $125/mo (5K) | Custom | Per-interaction |
| rentabot.chat | 14-day trial | $29/mo (3K msgs) | $79/mo (15K msgs) | $199/mo (50K msgs) | Flat-rate |
Prices reflect publicly available information as of March 2026. All platforms change pricing periodically, so verify current rates on their websites.
Hidden costs to watch for
The sticker price is rarely the whole story. Here are the extras that catch people off guard:
- Branding removal — most platforms show a "Powered by [Platform]" badge on the free and entry plans. Removing it costs $10-39/month extra on some platforms. rentabot.chat includes branding removal on all paid plans.
- Bring-your-own API key — some platforms require you to provide your own OpenAI API key, meaning you pay OpenAI directly on top of the platform fee. This can double your effective cost.
- Overage charges — exceeding your message limit either cuts off the chatbot (bad for customers) or bills you at inflated per-message rates. Check what happens when you go over.
- Premium model surcharges — want to use GPT-4 or Claude instead of GPT-3.5? Many platforms charge 5-20x more per message for premium models.
- Multiple chatbot fees — running chatbots on multiple websites often means paying for multiple subscriptions.
Pro tip
Calculate your cost per message, not just the monthly fee. A $99/mo plan with 2,000 messages costs $0.05 per message. A $49/mo plan with 500 messages costs $0.10 per message — twice as expensive on a per-use basis.
What affects the price?
Four factors drive your actual monthly cost:
- Message volume — the single biggest cost factor. Track your current support volume and estimate how many questions the chatbot will handle. Start with your FAQ traffic.
- Number of data sources — some platforms limit how many pages or documents you can index. If you have a large documentation site, check these limits carefully.
- LLM model choice — GPT-4o and Claude 3.5 deliver better answers but cost 10-20x more per token than GPT-3.5 or open source models. For most support queries, a smaller model works fine.
- Features needed — analytics, webhook integrations, custom branding, API access, and team seats often live behind higher-tier plans.
Which plan is right for your business?
Small business (under 1,000 messages/month)
You likely need 500-1,000 messages/month. An entry-level plan at $19-49/month covers this. Focus on platforms with easy setup and good free trials so you can validate the value before committing.
Growing business (1,000-10,000 messages/month)
Mid-tier plans at $49-149/month are your sweet spot. Pay attention to per-message costs at this volume — the difference between $0.03 and $0.10 per message is $700/month at 10,000 messages.
Enterprise (10,000+ messages/month)
At this scale, consider platforms with flat-rate pricing or volume discounts. Also evaluate self-hosting with Ollama — the hardware investment pays for itself quickly at high volume.
Frequently asked questions
How much does an AI chatbot cost per month?
Ranges from free (with limits) to $500+/month for enterprise. Most small businesses spend $19-49/month. Mid-size companies typically pay $99-199/month for higher message volumes and features.
What hidden costs should I watch for?
Branding removal fees ($10-39/month), bring-your-own API key requirements (you pay OpenAI directly), overage charges, and premium model surcharges for GPT-4 or Claude.
What's the cheapest AI chatbot platform?
Several platforms offer free tiers: Chatbase (100 msgs/month), Botpress (5 bots with limits), and rentabot.chat (14-day free trial). Paid plans start around $15-29/month across most platforms.
The cheapest chatbot isn't always the best value. Focus on cost per message, included features, and model quality. A slightly higher monthly fee with better answers will save you more in deflected support tickets. See the full platform comparison for a deeper look at features beyond pricing.
