Gusto API
Gusto exposes two documented REST surfaces: an App Integrations API with per-merchant OAuth 2.0 grants and an Embedded Payroll API with React SDK flows. Portal signup and the demo environment are self-serve; production access follows a commercial and security review with the partnerships team.
Frequently asked questions
Gusto scores A on Supergood's API Report Card. Gusto exposes two documented REST surfaces: an App Integrations API with per-merchant OAuth 2.0 grants and an Embedded Payroll API with React SDK flows. Portal signup and the demo environment are self-serve; production access follows a commercial and security review with the partnerships team.
Gusto has a workable official integration path. Most engineering teams can build against it directly. Open API: self-serve, documented, with SDKs
Gusto is a cloud-native payroll, benefits, and HR platform for small and mid-sized U.S. businesses.
Vertical: Enterprise / HR / ERP (SMB payroll & HR). Running scheduled and off-cycle payroll runs with automatic federal, state, and local tax filing. Generating and distributing W-2s, 1099s, and year-end tax forms.
Very high within the SMB payroll segment.
Employee PII (SSN, DOB, address, bank account, routing numbers). Wages, salaries, bonuses, commissions, equity comp. Federal/state/local tax withholdings and filings (941, 940, W-2, W-3, 1099-NEC, state UI).
Founded December 13, 2011 (~14 years old as of 2026). Cloud-native, mobile-friendly, modern React-based UI, and one of the more developer-forward SMB payroll vendors.
Supergood's grades measure one thing: can a customer's engineering team get their own data out programmatically? Supergood checks six things (whether a real API exists, how access is gated, data coverage, auth quality, docs and developer experience, and stability) and rolls them into a letter grade. Supergood re-verifies grades, and they only move on evidence.
Gusto has partial MCP support. Gusto publishes an official Dev Assistant MCP server, in open beta, for Gusto Embedded developers, with documented setup for Cursor, Claude Desktop, Windsurf, and VS Code. It covers only documentation search, API reference lookup, and code generation for the Embedded Payroll API, not access to payroll or company data.
Partially. MCP support for Gusto exists but is incomplete, so what MCP clients like Claude, Cursor, and Codex can reach depends on what the available server covers.