Company research · Watchlist
Retell AI
Voice agents by API — ~$60M annualized (est.) on ~$5M raised; headcount disputed 21–143.
Claimed capability · evidence still developing
The recorded proposition
Voice-agent platform grown to ~$60M annualized on ~$5M raised.
Index summary of the positioning; not an independent finding.
YC W24 voice/phone-agent API platform (founder Bing Wu) — the infrastructure behind many production phone agents. Growth is corroborated (Sacra estimates ~$60M annualized by Apr 2026, +650% YoY, on only ~$5.1M raised), but its famous efficiency claim is not: headcount reports range from 21 (Lean AI Leaderboard, Nov 2025) to 50 (YC directory) to 143 (Tracxn, Jun 2026) — treat ARR-per-human as disputed.
Where humans remain involved
Ongoing human hours, approval frequency and intervention rates have not been measured in this record. Reported team size describes the company, not the labor required to operate a customer business.
What still needs evidence
Establish a repeatable production workflow, identify the tasks people still perform, and measure cost, reliability and customer outcomes before drawing conclusions about business autonomy.
Recorded caveat: ARR is analyst estimate; ARR-per-human unreliable due to disputed headcount
Financial and team context
Reported figures retain their original scope. Revenue periods and headcount dates may differ; these are not a current audited financial statement.
- Annual run rate
- ~$60M annualized (Sacra est., Apr 2026)
As of 2026-04 · estimated · Source not rechecked
Source: Sacra · estimate ↗ - Reported team
- Disputed headcount
Observation date unknown · team unspecified · Source not rechecked
Source: Disputed: 21 (leaderboard) → 143 (Tracxn) ↗ - Funding as recorded
- ~$5.1MSource: Retell blog ↗
Financial and headcount history · 2 observations
Recorded dates show when an entry was added to this history. Source-check dates show when the publication was read; they do not establish that the figure is current or audited. Earlier observations and corrections remain visible.
Headcount · Disputed headcount
Observation date unknown · disputed · unknown
Scope: unknown · team unspecified · Recorded 2026-09-12 · Source checked not recorded · Published date unknown
Imported from the existing research record; source not rechecked during import. Missing dates remain unknown.
Disputed: 21 (leaderboard) → 143 (Tracxn) ↗Annual run rate · ~$60M annualized (Sacra est., Apr 2026)
As of 2026-04 · estimated · approximate
Scope: unknown · Recorded 2026-09-12 · Source checked not recorded · Published date unknown
Imported from the existing research record; source not rechecked during import. Missing dates remain unknown.
Sacra · estimate ↗
Round / transaction: $4.6M seed (Alt Capital lead; YC, Aaron Levie, Michael Seibel among angels)
Recorded date: 2024-08
Investors / backers: Alt Capital · Y Combinator · Carya Ventures
Pricing and commercial terms
Usage-based, ~$0.055/min platform fee.
Historical research snapshot. A pricing verification date is not recorded; confirm current plans, usage limits and additional costs with the provider before purchasing.
Founders and recorded roles
Bing Wu
Co-founder & CEO; YC W24; pivoted from an AI dubbing platform.
Recorded technology stack
No stack details recorded.
Components listed in the research record; integrations have not been independently tested here.
Research timeline
2026-04
Sacra estimates ~$60M annualized revenue, up ~650% YoY, on ~$5.1M total raised. Headcount disputed across sources (21–143) — efficiency claims flagged.
Direct article link not recorded.
Sources and coverage limits
This profile brings together the existing Index research. Company announcements, sponsored articles and founder interviews can establish what was said; they do not independently prove sustained autonomy or revenue.