Payroll systems · Justworks
Justworks
Justworks's own documentation covers employees, pay statements and deduction write through the API. Access: Partner program required.
Integration method grade A · field-level docs publicly readable · last verified 2026-09-26 · Justworks API reference — Deductions
What the API lets you do
| Question | Answer | Conf | What the documentation says |
|---|---|---|---|
| How do you get API access? | Partner program required | D | 'OAuth application creation is not self-service. If you are an approved partner, the Justworks team will work with you to get set up.' The reference itself is public. Source |
| Can you read employees and pay rates? | Yes — members | D | GET /v1/members returns job_title, employment_start_date, current_pay and pay and employment history; PATCH updates only job title, department and manager. Source |
| Can you read pay statements? | Yes — paystubs | D | GET /v1/payrolls and /v1/paystubs/{id} return earnings, employee deductions (pretax, tax, aftertax) and employer contributions. Source |
| Can you write a deduction? | Yes — REST API | D | POST, PUT and PATCH /v1/deductions/cancel (scope deductions:write), with per-item idempotency keys. Source |
| Can you write a direct deposit account? | Not offered | — | Only the company bank account is readable; no employee bank or direct-deposit endpoint. |
| Can you read W-2s? | Not offered | — | No W-2 or tax-document endpoint; only the member tax ID is returned. |
| Can you read hours worked? | Time off only | — | Time-off requests, policies and balances only; no worked-hours or timesheet endpoint. |
| Does it push change events? | Unverified | U | Webhooks are not in the public reference navigation. |
| How does an integration authenticate? | OAuth 2.0 authorisation code | D | Authorisation-code flow; access tokens last 24 hours, refresh tokens 30 days; scopes include deductions:read and deductions:write. Source |
Deduction write, in detail
For benefits, HSA/FSA and 401(k) integrations. 3 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 | Yes — GET /v1/deductions | D | Returns member, deduction_type_code, frequency, amount_type, amount, start_date and end_date. |
| Deduction write | API (REST, batch) | D | POST, PUT and PATCH /cancel; create requires member, type code, frequency, description, amount type, amount and start date; results are per item. |
| Pre-tax vs post-tax at write | Not represented at write | D | The write has no taxability field, only deduction_type_code; paystubs label deductions pretax, tax or aftertax. |
| Amount vs percent | Both — fixed or percent | D | amount_type fixed (in cents) or percent (four-decimal precision: 3.7% = 37000). |
| Effective dating | start_date / end_date | D | start_date required, end_date optional, with frequencies from one_time to every_paycheck and split schedules. |
| Retro adjustment | Unverified | U | No public statement on backdated start dates or retro adjustment. |
| Employer contribution | Not supported in write | D | The deduction write has no employer-contribution field; employer contributions appear read-only on paystubs. |
| Code taxonomy shape | Unverified | U | GET /v1/deduction-types returns codes 'for the current company' without saying whether they are Justworks-fixed or company-defined. |
| Auth model | OAuth 2.0 | D | Company access token with deductions:read or deductions:write. |
| Data freshness | Unverified | U | No latency or freshness statement located. |
D vendor-documented · U unverified · — not offered. See every payroll system side by side in the Payroll API Capability Matrix.