Within this cluster, the accessible end is self-serve and the enterprise end is quote-only. Botpress gives the most generous free plan — 100 conversations/month with AI included — then jumps to Plus $150/month, Team $750/month and Built For You $1,650/month, all conversation-priced with LLM costs passing through; its May 2026 restructure added unlimited bots and Always Alive on every paid tier, so ignore the older Creator $89 / Pro $495 numbers still floating on third-party sites. Chatbase gives a free 50-message/month tier for one member, then Hobby $40/month ($15 annual), Standard $150 ($99) and Pro $500 (about $400 annual) — credit-based, so premium models burn credits faster and the real messages-per-credit varies. ResolveAI has no free tier but the cheapest paid bridge in the cluster: a 10-day no-card trial, then Basic $9/month (2,000 AI messages), Enhanced $29 and Expert $79 (unlimited, on your own OpenAI API key), with annual billing giving two months free and branding removal a $39/month add-on. Ada and Drift have no free tier and no self-serve plan at all — both are enterprise-quoted. Ada scales with resolved-conversation volume, with reported deals from roughly $30K-$150K+/year, and sits on top of an existing helpdesk. Drift, acquired by Salesloft in 2024 and now sold inside its revenue platform, is sales-led and billed annually only: Premium runs about $2,500/month (~$30K/year), Enterprise typically $80K-$150K/year, with implementation often adding $5K-$15K. So the free-or-trial lane is Botpress and Chatbase, with ResolveAI's trial as the cheapest paid bridge — and the free tiers are windows, not lanes: production autonomy and volume are where the bill starts. Pricing verified against official pages (2026-09-21).
Free = 100 conversations/mo with AI usage included and the full builder; 3 seats on free. The most usable free tier of the cluster.
Free tier: Yes
Paid from: $150/mo (Plus) (Conversation-priced, not seat-priced (LLM costs pass through at vendor rates). May 2026 update: unlimited bots on paid plans, raised storage, 'Always Alive' on all paid tiers. Free = 100 conversations/mo. Note: third-party sources still list the older Creator $89/Pro $495 tiers — the official May 2026 blog is authoritative.)
Botpress is the open-source, developer-oriented AI-agent and AI-native helpdesk platform — visual flow builder plus GPT-native nodes; free 100 conversations/mo, Plus from $150/mo (May 2026 pricing).
Free = 50 messages/mo, 1 member, basic models, 400KB training. Hobby $40/mo (or $15/mo annual) removes the cap.
Free tier: Yes
Paid from: $15/mo (Hobby, annual) (Credit-based: different models consume credits at different rates (premium models burn faster), so actual responses-per-credit varies. Free = 50 msg/mo, 1 member; paid tiers add message volume, API access, integrations and team seats. 20% off yearly. Branding removal and custom domain are paid add-ons.)
Chatbase is the no-code AI chatbot trained on your own data — deploy a knowledge-base agent to your site, WhatsApp or voice; credit-based plans from a free 50-message tier up to $40/mo Hobby.
No free tier, but a 10-day trial on the $9/mo Basic — the cheapest self-serve entry point in the cluster.
Free tier: No — trial only · 10-day free trial (no card)
Paid from: $9/mo (Basic) (Message-metered per plan: Basic 2,000 AI messages/mo, Enhanced 4,000, Expert unlimited (own OpenAI API key). Additional bots cost extra; branding removal is a $39/mo add-on. Cheapest paid entry of the cluster; 10-day trial, cancel anytime.)
ResolveAI trains a 24/7 custom AI chatbot on your own website, docs and live data, deployable across WhatsApp, Messenger and Slack; cheap entry at $9/mo (Basic) with a 10-day trial.
Ada is quote-only with no self-serve or free tier — a bridge to it is a sales engagement, not a plan.
Free tier: No — trial only
Paid from: Quote-based (reported deals from ~$30K-150K+/yr) (No public list price and no self-serve plan: enterprise-only, custom-quoted and scaling with resolved-conversation volume; reported deals start around $30K-$150K+/year. Sits on top of an existing helpdesk (Zendesk/Salesforce). Deployed by Meta, Verizon, Air Asia and Shopify. No free tier.)
Ada is the autonomous AI customer-service agent for enterprise CX — a reasoning engine that resolves tier-1 tickets across chat/email/voice/SMS/WhatsApp; quote-based, no self-serve free tier.
Drift is sales-led from ~$2,500/mo annual with a 30-day trial; no free tier. Out of scope for the low-cost lane.
Free tier: No — trial only · 30-day free trial (sales-led)
Paid from: ~$2,500/mo (Premium, billed annually) (No public self-serve pricing: enterprise sales-led, billed annually only. Acquired by Salesloft in 2024 and now sold inside the Salesloft revenue platform. Implementation/onboarding commonly adds $5K-$15K. No free tier as of 2026.)
Drift (now part of Salesloft) is the conversational-marketing platform for lead qualification and meeting booking — AI chatbots plus live chat; enterprise-priced from ~$2,500/mo, no free tier.
Bottom line: Bottom line: the self-serve lane of this cluster is Botpress (free 100 conversations/mo, the most generous), Chatbase (free 50 messages/mo) and ResolveAI (10-day trial on a $9/mo entry). Ada and Drift have no free tier — they are enterprise-quoted. For a real $0 start, Botpress; for the cheapest paid bridge, ResolveAI's trial. Treat free tiers as trial windows, not permanent lanes.
Botpress (free 100 conversations/mo, AI included) and Chatbase (free 50 messages/mo). ResolveAI is a 10-day trial, not a free tier; Ada and Drift have no free option.
ResolveAI Basic at $9/mo (or $90/yr). Chatbase Hobby is $40/mo monthly or $15/mo annual. Botpress Plus is $150/mo after the May 2026 restructure.
Botpress free includes the AI helpdesk builder and 100 conversations — usable for light support. Chatbase free is capped at 50 messages. Heavier autonomy and volume need paid plans or the enterprise tools.