Rational
Rational is a YC Summer 2026 (S26) company. Based in San Francisco, CA, USA. Team of 2.
About Rational
Summary
Rational builds AI agents that work inside accounting firms, handling month-end close, tax preparation, and client follow-up. The agents onboard themselves to a firm, build a knowledge base of the firm's clients and processes, and execute the work that staff accountants and managers currently do. The target customer is the accounting firm looking to run client engagements without adding headcount.
Go-to-market
Accounting firms are the buyer; onboarding is initiated through a direct conversation with the Rational team, as shown by the "Talk to us" call to action on the site.
From the Y Combinator listing
AI Employees for Accounting
Rational builds AI coworkers for accounting firms. Our agents onboard themselves to the firm, build a company brain, and do the work, from month-end close to tax prep. In addition, they follow up with clients and communicate with the right members of your team.
Facts
- B2B / B2B -> Operations
- San Francisco, CA, USA
- 2
- Active
- Early
Founders (2)
- Christ Xu
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