Payroll systems · Paychex
Paychex
Paychex's own documentation covers employees, pay statements, deduction write, bank account write, hours and webhooks through the API. Access: Client app key or Partner Program.
Integration method grade ? · field-level docs NOT publicly readable · last verified 2026-09-26 · Paychex Developer Center (partner-gated)
What the API lets you do
| Question | Answer | Conf | What the documentation says |
|---|---|---|---|
| How do you get API access? | Client app key or Partner Program | D | Clients create an app in Paychex Flex (Company Settings > Connected Applications) for an API key; partners go through the Paychex Partner Program — questionnaire, review, sandbox, demo, then production key and secret. Source |
| Can you read employees and pay rates? | Yes — REST read and write | D | Worker resource with compensation, federal and state tax and direct deposit sub-resources, added (POST) and updated (PATCH) by workerId. Source |
| Can you read pay statements? | Unprocessed checks only | D | POST, GET and DELETE for unprocessed checks with earnings and deductions, plus pay periods and pay components. No public page for reading processed check history or pay stubs was found. Source |
| Can you write a deduction? | Yes — recurring deductions | D | Benefits Administration: createWorkerRecurring adds a deduction to a worker and updateWorkerRecurring updates it; one-time deductions can be placed on unprocessed checks. Source |
| Can you write a direct deposit account? | Yes — add / update / remove | D | The Direct Deposit use case lets you retrieve, add or update several direct deposits at once, or retrieve, update or remove a single one. Source |
| Can you read W-2s? | Unverified | U | Worker federal and state tax setup is exposed, but nothing about reading W-2s or tax documents. |
| Can you read hours worked? | Yes — separate T&A API | D | Send and retrieve punch and scheduling data through a separate Time & Attendance API (the Stratus Time portal), which does not follow the Developer Center's patterns. Source |
| Does it push change events? | Yes — webhooks | D | Register with POST /management/hooks; domains include worker demographics, compensation, employment, tax and assignment changes, client access and CLT_PYRN (payroll complete). Source |
| How does an integration authenticate? | OAuth 2.0 bearer (key/secret) | D | Key and secret in the request body return a bearer token that expires in 60 minutes and cannot be refreshed. Source |
Deduction write, in detail
For benefits, HSA/FSA and 401(k) integrations. 9 of 10 fields are unverified — no public source states the answer. Compare every system on the deduction write detail page.
| Field | Value | Conf | Note — and what a correct answer needed |
|---|---|---|---|
| Deduction read | Unverified | U | A developer centre exists at developer.paychex.com, but field-level API documentation is not publicly readable: third parties state access requires becoming an approved Paychex partner. |
| Deduction write | API — recurring deductions | D | Re-checked 2026-09-26. The Benefits Administration use case documents createWorkerRecurring and updateWorkerRecurring to add and update a worker deduction; one-time deductions can be placed on unprocessed checks. Field-level shape not rendered to a non-browser fetch. |
| Pre-tax vs post-tax at write | Unverified | U | No public field-level specification. |
| Amount vs percent | Unverified | U | No public field-level specification. |
| Effective dating | Unverified | U | No public field-level specification. |
| Retro adjustment | Unverified | U | No public field-level specification. |
| Employer contribution | Unverified | U | No public field-level specification. |
| Code taxonomy shape | Unverified | U | No public field-level specification. |
| Auth model | Unverified | U | No public field-level specification. |
| Data freshness | Unverified | U | No public field-level specification. |
D vendor-documented · U unverified · — not offered. See every payroll system side by side in the Payroll API Capability Matrix.