Sierra vs Ultimate.ai — Pricing, Plans, and Verified Costs (2026)
Both Sierra and Ultimate.ai use custom pricing — request quotes from each to compare.
See price history: Sierra · Ultimate.ai
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.
- Sierra (Per Usage) — Sierra bills purely on usage. There is no fixed per-seat fee, so the monthly cost depends entirely on how much you consume.
- Ultimate.ai (Per Usage) — Ultimate.ai bills purely on usage. 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.
AI-native customer experience platform founded by Bret Taylor (ex-Salesforce COO) and Clay Bavor (ex-Google). Positioned to compete with Ada + Decagon at the strategic enterprise level. All pricing custom-quoted, reported deals $200K-1M+/year. Customers include WeightWatchers, SonderMind, SoFi.
AI customer service automation platform, acquired by Zendesk in March 2024. Now sold primarily as Zendesk AI + Ultimate agents. All pricing rolled into Zendesk enterprise deals; standalone pricing was reported at $500-2000/mo per language before the acquisition.
All plans compared
| Tier role | Plan | Sierra monthly | Sierra annual | Ultimate.ai monthly | Ultimate.ai annual |
|---|---|---|---|---|---|
| Enterprise | Enterprise / — | 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
Sierra is worth it if… Sierra is only worth engaging with if you're a mid-market or enterprise support org running a serious evaluation of autonomous AI agents — the co-founders' pedigree (Bret Taylor ex-Salesforce COO) opens doors that other startups can't. Deal size $200K-1M+/year.
Ultimate.ai is worth it if… ai (now Zendesk AI) is worth it if you're already deep on Zendesk and want to add AI agent automation without a separate vendor. ai purchases are being funneled into Zendesk Suite AI packages.
Bottom line: Similar positioning, closer to a preference call than a strategic one.
Choose Sierra over Ultimate.ai if…
Choose Sierra if…
- You want to pay only for actual usage (per usage, custom pricing).
- You match the profile Sierra is built for: only worth engaging with if you're a mid-market or enterprise support org running a serious evaluation of autonomous AI agents — the co-founders' pedigree (Bret Taylor ex-Salesforce COO) opens doors that other startups can't.
- You need a general-purpose customer support option rather than a vertical-specific one.
Choose Ultimate.ai if…
- You want to pay only for actual usage (per usage, custom pricing).
- You match the profile Ultimate.ai is built for: Ultimate.
- You need a general-purpose customer support option rather than a vertical-specific one.
At a glance
| Sierra | Ultimate.ai | |
|---|---|---|
| Free plan | No | No |
| Entry price | Custom | Custom |
| Enterprise available | Yes | No |
| Pricing model | Per Usage | Per Usage |
| Last verified | September 20, 2026 | — |
| Full pricing | View full pricing | View full pricing |
Pricing last verified September 20, 2026. Tracked daily.