Cartesia vs Retell AI — Pricing, Plans, and Verified Costs (2026)
Cartesia starts at $5/mo. Retell AI starts at Free. Retell AI is $5/mo cheaper on the entry tier than Cartesia.
How pricing works
These two tools don't price the same way, so the headline numbers below aren't directly comparable until you plug in your own volume.
- Cartesia (Hybrid) — Cartesia is hybrid: a fixed subscription from $5/mo plus metered usage on top. Your real bill moves with volume, not seat count.
- Retell AI (Per Usage) — Retell AI bills purely on usage — PAYG. There is no fixed per-seat fee, so the monthly cost depends entirely on how much you consume.
Per-minute, per-credit and per-token rates exclude any downstream model, speech or telephony costs unless the vendor states otherwise.
Voice AI research lab building state-of-the-art speech synthesis models (Sonic) with ultra-low latency (<100ms). Usage-based pricing: pay-per-character generation, entry rate around $0.017/1K characters. Enterprise custom for volume. Popular with voice agent developers who need faster-than-ElevenLabs synthesis for real-time conversations.
AI voice agent platform. PAYG at $0.07+/min base ($10 free credits, 20 free concurrent calls); real all-in cost $0.13–0.31/min. Enterprise drops to $0.05+/min base rate. Supports GPT-5.x variants and Claude 4.5/4.6 Sonnet; Fast Tier LLM adds 1.5–2× charge for lower latency. Direct competitor to Vapi and Bland AI.
All plans compared
| Tier role | Plan | Cartesia monthly | Cartesia annual | Retell AI monthly | Retell AI annual |
|---|---|---|---|---|---|
| Free / starter | Free / PAYG | Free | Free | Free | Free |
| Entry paid | Pro / — | $5 | $4 | — | — |
| Mid tier | Startup / — | $49 | $39 | — | — |
| Pro / power | Scale / — | $239 | $239 | — | — |
| Enterprise | Enterprise | Custom | Custom | Custom | Custom |
Tier names differ across vendors. Rows are aligned by tier role, not name. Full tier structures on each tool's page.
What each is best for
Cartesia is worth it if… developers building real-time voice agents where sub-100ms TTS latency matters (voice interruption handling, conversational feel). Sonic model is competitive with ElevenLabs on quality and faster on latency.
Retell AI is worth it if… developers who want a slightly more opinionated voice stack than Vapi — bundled defaults that ship faster, with paid unlocks for premium voices and Fast Tier LLM latency. Free credits make prototyping frictionless.
Bottom line: Choose based on how you want to pay — Cartesia is hybrid, Retell AI is per usage.
Choose Cartesia over Retell AI if…
Choose Cartesia if…
- You're fine with a base subscription plus metered usage on top (from $5/mo).
- You match the profile Cartesia is built for: developers building real-time voice agents where sub-100ms TTS latency matters (voice interruption handling, conversational feel).
- You need a general-purpose voice agents & speech/audio option rather than a vertical-specific one.
Choose Retell AI if…
- You want bundled defaults that ship faster than assembling components yourself.
- You're building voice agents where developer experience and UI matter more than stack flexibility.
- You want premium voices and low-latency model tiers behind a simple paid unlock.
At a glance
| Cartesia | Retell AI | |
|---|---|---|
| Free plan | Yes | Yes |
| Entry price | $5/mo | Free |
| Enterprise available | Yes | Yes |
| Pricing model | Hybrid | Per Usage |
| Last verified | September 20, 2026 | September 10, 2026 |
| Full pricing | View full pricing | View full pricing |
Pricing last verified September 20, 2026. Tracked daily.