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Head to head · Payroll records · October 2026 research run

Gusto vs PayFit

Gusto scores 63.3 (B) on agent readiness against PayFit's 55.5 (C), and leads in 5 of 7 scored categories. PayFit leads on reliability and transparency & trust. Both do payroll records.

Best payroll APIs and embedded payroll for AI agents · All 55 payroll comparisons

GustoGusto, Inc. · HTTP API B63.3/100#399 of 950 PayFitPayFit SAS · HTTP API C55.5/100#656 of 950

Which one, for what

Gusto B

Good for A software platform that wants to run US payroll for its own customers and can pass Gusto's partner reviews.

Ahead on

  • Schema & documentation, 86 against 78
  • Agent ergonomics, 82 against 51
  • Security & auth, 60 against 51
  • Payments & pricing, 15 against 10
  • Maintenance & community, 76 against 28

Watch for

Production keys need commercial, security and implementation reviews with Gusto's partnerships team, and the docs say not all use cases are supported

PayFit C

Good for An agent working for an employer that already runs payroll on PayFit in France, the UK or Spain and needs employees, contracts, payslips, absences or the payroll journal.

Ahead on

  • Reliability, 79 against 58
  • Transparency & trust, 70 against 61

Watch for

No operation runs, previews or approves a payroll. The API reads payroll status, payslips and accounting exports

Score by category

CategoryWeight this runGustoPayFitEdge
Reliability16%205879PayFit +21
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28678Gusto +8
Agent ergonomics13%16.28251Gusto +31
Security & auth14%17.56051Gusto +9
Payments & pricing10%12.51510Gusto +5
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.87628Gusto +48
Transparency & trust7%8.86170PayFit +9
Negative events≤1500
Total63.3 · B55.5 · C

Facts side by side

FactGustoPayFit
KindHTTP APIHTTP API
VendorGusto, Inc.PayFit SAS
Hosted endpointno (local only)no (local only)
TransportsHTTPHTTP
AuthOAuthOAuth or key
PricingPaidPaid
x402nono
LicenceProprietary service under Gusto's API Policy and Developer Terms of Service. The API clients on GitHub are MIT, and the React SDK and the Gusto CLI are Apache-2.0Proprietary service under PayFit's general terms of service
Read-only variant documentednono
llms.txtyesyes
Last release2026-10-012026-07-23
Terms last updatedcouldn't be read2026-06-15
Privacy policy last updatedno document linked2026-06-15
Customer content may train modelscouldn't be readnot found in the text
Terms restrict automated accesscouldn't be readnot found in the text
Terms restrict benchmarkingcouldn't be readyes
Terms or service can change without noticecouldn't be readyes
Arbitration or class-action waivercouldn't be readnot found in the text
Popularity2 stars, 25k npm/wknone

Verdicts

Gusto

This listing covers the Embedded Payroll API. Every reference page carries an OpenAPI 3.1 definition, payroll is calculated as a preview before submission, and each API version gets 12 months of deprecation support. Production needs commercial and security approval, no price was readable, and the status page lists 11 incidents between 14 July and 5 October 2026, five marked major.

PayFit

A public OpenAPI 3.0 file, llms.txt and scoped keys let a paying customer's agent read payroll outputs and write absences. The API cannot run or approve a payroll, new partner integrations are not being accepted, and no idempotency keys or SDKs were found.

Before you call either

Gusto

  1. Develop against https://api.gusto-demo.com. Production at https://api.gusto.com needs keys Gusto issues after its reviews
  2. Send X-Gusto-API-Version: 2026-06-15 on every call. Without it the application's minimum version applies
  3. Send the resource's current version with every PUT, and only the fields to change. A stale version returns 409
  4. Calculate and submit return 202. Poll GET on the payroll until calculated_at is set or the status is processed, and read submission_blockers first
  5. For a company already on Gusto, the Embedded API is the wrong route. Use the Gusto CLI or the MCP server at https://mcp.api.gusto.com, which draft payroll but can't submit it

PayFit

  1. Have a company admin create the key at app.payfit.com/integrations/hub/api with only the scopes the task needs. The key is shown once
  2. POST the key to https://oauth.payfit.com/introspect to get company_id, then call https://partner-api.payfit.com/companies/{companyId}/...
  3. Page lists with nextPageToken and maxResults, which defaults to 10 and stops at 50
  4. Check before repeating a failed POST. There is no idempotency key, and POST /absences creates an absence that is already validated
  5. A collaborator or contract created through the API stays incomplete until an HR admin finishes it in the PayFit app, and a new contract takes 2 to 5 minutes to appear

Questions

Which is better for AI agents, Gusto or PayFit?

Gusto scores 63.3 (B) on agent readiness against PayFit's 55.5 (C), and leads in 5 of 7 scored categories. PayFit leads on reliability and transparency & trust.

Do Gusto and PayFit need an API key?

Gusto uses an OAuth sign-in. PayFit takes an API key or an OAuth sign-in.

Can an agent call Gusto and PayFit without installing anything?

No hosted endpoint is listed for Gusto. No hosted endpoint is listed for PayFit.

Other comparisons with Gusto or PayFit

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