Letterbook is an AI-native customer support platform positioned as an alternative to Zendesk, Freshdesk, and Intercom for lean teams. Founded in 2023 by Yale and Berkeley dropouts Dawson Chen and Ethan Hou, who had previously grown an earlier product to 100,000 users, Letterbook went through Y Combinator's Summer 2023 batch.
The platform connects to a company's inbox, product database, and Stripe account, then uses large language models guided by founder-defined playbooks to draft or fully resolve tickets for common situations like refunds, login issues, or bug reports. Support agents review AI-generated replies through a contact-center-style interface rather than writing every response from scratch.
Letterbook suits startups and small support teams that want automation without the overhead of enterprise helpdesk software built for much larger organizations. Pricing starts at the Starter plan at $50 a month, with a Growth plan at $200 a month and custom Enterprise pricing for higher ticket volumes, SSO, and dedicated support; a 7-day free trial requires no credit card, but there is no permanent free tier.








