- Headquarters
- San Francisco, California
- Employees
- 51–200
- Founded
- 2019
- Business Model
- B2B
- Website
- mainstreet.com
- Total Funding
- $60.0M
- Last Round
- $60.0M Series AMar 2021
- Rounds
- 3
About
MainStreet is a financial technology platform that helps startups and small businesses automate their back office and unlock hidden tax savings. Its AI-powered system scans payroll and accounting data to identify eligible federal, state, and local tax credits—including R&D tax credits—and manages the legal workflows to claim them. Beyond tax credits, MainStreet offers integrated bookkeeping, business banking, and financial management tools. The company was founded in 2019, acquired Capbase (company formation) in 2025, and was itself acquired by Employer.com in May 2025. It is headquartered in San Francisco, California.
Summary
MainStreet is a Fintech company based in San Francisco, United States, founded in 2019. It has raised $60.0M in total across 3 rounds, most recently a $60.0M Series A round in Mar 2021. Investors include Gradient Ventures, SignalFire and Reshape.
Tech & App Stack
2 technologies & apps tracked
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Funding History
Mar 2021
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Seed through Series A — per-round amounts, valuations, and who invested in each round.
Investors
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