Callab AI
Callab AI is a YC Spring 2026 (P26) company. Based in San Francisco, CA, USA. Team of 7.
About Callab AI
Summary
Callab AI builds AI voice agents that plug directly into on-premises PBX systems, including Avaya, Cisco UCM, and Mitel, automating inbound call volume without replacing existing infrastructure. Call centers running legacy telephony have had no path to voice AI short of a full migration; Callab eliminates that barrier. Customers include large consumer brands across multiple continents.
Go-to-market
Callab sells to B2B call center operators already locked into on-prem telephony stacks, integrating at the infrastructure level so buyers need no migration project to get started.
From the Y Combinator listing
AI voice agents for on-prem telephony stack.
58% of the $400B call center industry runs on on-prem phone systems, and until now bringing AI voice automation to them meant ripping out their entire infrastructure first. That's the largest unserved segment in the market. Callab AI connects directly to legacy PBX systems like Avaya, Cisco UCM, and Mitel, and automates up to 70% of call volume with zero migration needed. We plug into these environments without requiring a rip-and-replace. We serve clients across three continents, including brands like Dunkin Donuts.
Facts
- B2B / B2B -> Operations
- San Francisco, CA, USA
- 7
- Active
- Early
Founders (2)
- Chehir Dhaouadi
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