Welcome to SingleFile
Welcome to the SingleFile API — the fastest way to automate business entity formation, EIN filing, document management, and annual report compliance across all U.S. jurisdictions.
What You Can Do
Incorporate LLCs, Corporations, and more in any U.S. state — programmatically.
Obtain federal Employer Identification Numbers directly through the API.
Upload, search, and download formation documents and compliance records.
Stay in good standing with automated annual report filings across jurisdictions.
Getting Started in 4 Steps
┌──────────────┐ ┌──────────────┐ ┌──────────────┐ ┌──────────────┐
│ 1. Get Your │ │ 2. Get a │ │ 3. Make Your │ │ 4. Build │
│ Credentials │───>│ Bearer Token │───>│ First Call │───>│ Workflows │
└──────────────┘ └──────────────┘ └──────────────┘ └──────────────┘
SingleFile POST /o/token/ GET /entities/list Formation,
provides your with client_id to verify EIN, Annual
client_id & & client_secret everything works Reports & more
client_secretNew here? Jump straight to the Quick Start to make your first API call in under 5 minutes.
Environments
| Environment | Base URL | Purpose |
|---|---|---|
| Sandbox | https://api.demo.singlefile.ai/external-api/v1/ | Development & testing — no real filings |
| Production | https://api.app.singlefile.io/external-api/v1/ | Live filings with state authorities |
Always develop and test against the Sandbox environment first. Sandbox runs the same API and accepts orders, but nothing is fulfilled or submitted to a state or the IRS. All examples in these guides use the Sandbox host.
Explore the Docs
Fundamentals
Workflow Guides
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Updated 7 days ago