Justworks is a New York City-based Professional Employer Organization (PEO) and small-business HR platform. It bundles payroll, tax filing, multi-state compliance, large-group medical/dental/vision benefits, 401(k) administration, workers comp, time tracking, and HR consulting into a single per-employee-per-month subscription. Justworks operates four primary products: Justworks Payroll (standalone payroll), Justworks PEO Basic, Justworks PEO Plus (PEO with included benefits package), and Justworks EOR International for hiring full-time employees abroad without a local entity. Justworks exposes a Partner API at public-api.justworks.com for approved integration partners, covering Members, Company, Payroll, Paystubs, Deductions, Time Off, and Webhooks. The API uses OAuth 2.0 authorization-code grant, cursor pagination, signed at-least-once webhooks, and zero-decimal currency representation. Deductions is the primary write surface; everything else is read-only.
Justworks publishes 11 API contracts indexed on the APIs.io network, including Members API, Company API, Deductions API, and 8 more. Tagged areas include PEO, Payroll, Human Resources, Benefits, and Health Insurance.
The Justworks catalog on APIs.io includes 1 JSON-LD context and 1 Spectral governance ruleset.
Justworks’ developer surface includes authentication, documentation, developer portal, getting-started guide, pricing, engineering blog, YouTube channel, and 19 more developer resources.
Regulatory Posture applies to this provider. Its tags matched the
Employment & Payroll regime, so
Regulatory Posture carries 15 points of the composite.
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applicability map is public and we will correct it.
Create-or-Update Ergonomics applies to this provider. This API accepts writes, so it
carries 10 points of the composite. It is scored from the published contracts
themselves: whether a caller can create-or-update in one call, whether the write accepts a key the caller already
holds, and whether the response says which branch ran. Without that, every write needs a search-and-branch in
front of it, and the first time that check is skipped a duplicate record is created.
Scored against the observed mean rather than raw — a provider at the catalog average is unchanged by this facet,
not penalised by it.
The six quality facets above are damped to 75 points between them,
because the conditional facet above carries the other
25. That is why each facet's contribution is shown against a damped
maximum: raising a quality facet moves the composite by 75% of its nominal
weight, not 100%. The full arithmetic is at apis.io/rating/.
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Agent readiness — checks not met, largest first (exact, from this profile):
Idempotency+9 pts — OpenAPI mutating operations declare an idempotency key — a header, a request-body property, or a named de-duplication token whose own description says so (verified); else common[].type matches /idempoten/i (documented)
Stable Error Semantics+8 pts — OpenAPI $refs a shared error schema across 4xx/5xx responses (verified), else common[].type includes ErrorCatalog / ErrorCodes / DeclineCodes
A2A Agent Card+8 pts — a2a/-a2a.yml manifest, graded on conformance.grade against A2A 1.0.0
Request/Response Examples+7 pts — share of operations carrying request/response examples; else an Examples / Code Samples link
Standards this provider implements or carries. De facto ones are profiled and measured by the API Commons; formal ones come from the standards directory and are linked by the provider's own tags. The evidence column says how each claim was established — not that it was made.
Read employee, contractor, and member information from the Justworks Partner API. Provides access to member profiles, employment history, pay history, custom-field values, and U...
Read company-level data from the Justworks Partner API including company identity, departments, offices, bank account on file (masked), verified business information, custom-fie...
Manage employee deductions — list deduction types, create one-time and recurring deductions, update existing deductions, and cancel deductions in bulk. The primary write surface...
Manage Justworks Partner API webhooks. Justworks signs every request, delivers events at-least-once with automatic retries, and closes a webhook on sustained failures (resumable...
aid: justworks
url: https://raw.githubusercontent.com/api-evangelist/justworks/refs/heads/main/apis.yml
apis:
- aid: justworks:justworks-members-api
name: Justworks Members API
tags:
- Human Resources
- PEO
- Members
- Employees
tags_raw:
- HR
- PEO
- Members
- Employees
humanURL: https://public-api.justworks.com/v1/docs
properties:
- url: https://public-api.justworks.com/v1/docs
type: Documentation
- url: openapi/justworks-members-api-openapi.yml
type: OpenAPI
- url: json-schema/justworks-member-schema.json
type: JSONSchema
- url: json-ld/justworks-context.jsonld
type: JSONLD
description: 'Read employee, contractor, and member information from the Justworks Partner API. Provides access to
member profiles, employment history, pay history, custom-field values, and U.S. tax identifiers
(SSN) for domestic members. This is the canonical workforce-truth surface a partner integrates
against. Uses cursor pagination with a hard cap of 100 items per page.
'
- aid: justworks:justworks-company-api
name: Justworks Company API
tags:
- Human Resources
- PEO
- Company
tags_raw:
- HR
- PEO
- Company
humanURL: https://public-api.justworks.com/v1/docs
properties:
- url: https://public-api.justworks.com/v1/docs
type: Documentation
- url: openapi/justworks-company-api-openapi.yml
type: OpenAPI
description: 'Read company-level data from the Justworks Partner API including company identity, departments,
offices, bank account on file (masked), verified business information, custom-field definitions,
and the jurisdictions in which the company operates.
'
- aid: justworks:justworks-deductions-api
name: Justworks Deductions API
tags:
- Deductions
- Payroll
- PEO
humanURL: https://public-api.justworks.com/v1/docs
properties:
- url: https://public-api.justworks.com/v1/docs
type: Documentation
- url: openapi/justworks-deductions-api-openapi.yml
type: OpenAPI
- url: json-schema/justworks-deduction-schema.json
type: JSONSchema
description: 'Manage employee deductions — list deduction types, create one-time and recurring deductions,
update existing deductions, and cancel deductions in bulk. The primary write surface of the
Justworks Partner API. Each item carries a partner-supplied operation_id for idempotency.
'
- aid: justworks:justworks-webhooks-api
name: Justworks Webhooks API
tags:
- Webhook
- Event
- Human Resources
tags_raw:
- Webhooks
- Events
- HR
humanURL: https://public-api.justworks.com/v1/docs
properties:
- url: https://public-api.justworks.com/v1/docs
type: Documentation
- url: openapi/justworks-webhooks-api-openapi.yml
type: OpenAPI
- url: json-schema/justworks-webhook-event-schema.json
type: JSONSchema
description: 'Manage Justworks Partner API webhooks. Justworks signs every request, delivers events at-least-once
with automatic retries, and closes a webhook on sustained failures (resumable via API). Event types
cover member.profile.*, member.employment_state.termination_*, and department.* lifecycle changes.
A Tour-environment simulate endpoint allows partners to validate their listener without real data.
'
- aid: justworks:justworks-deduction-types-api
name: Justworks Deduction Types API
description: Read access to Justworks deduction type catalog
humanURL: https://public-api.justworks.com/v1/docs
tags:
- Deduction Types
properties:
- type: OpenAPI
url: openapi/justworks-deduction-types-api-openapi.yml
- type: Documentation
url: https://public-api.justworks.com/v1/docs
- type: JSONSchema
url: json-schema/justworks-payroll-schema.json
- type: JSONSchema
url: json-schema/justworks-paystub-schema.json
- type: JSONSchema
url: json-schema/justworks-time-off-request-schema.json
- aid: justworks:justworks-payrolls-api
name: Justworks Payrolls API
description: Read access to payroll runs and per-payroll fees
humanURL: https://public-api.justworks.com/v1/docs
tags:
- Payrolls
properties:
- type: OpenAPI
url: openapi/justworks-payrolls-api-openapi.yml
- type: Documentation
url: https://public-api.justworks.com/v1/docs
- type: JSONSchema
url: json-schema/justworks-payroll-schema.json
- type: JSONSchema
url: json-schema/justworks-paystub-schema.json
- type: JSONSchema
url: json-schema/justworks-time-off-request-schema.json
- aid: justworks:justworks-paystubs-api
name: Justworks Paystubs API
description: Read access to per-member paystubs
humanURL: https://public-api.justworks.com/v1/docs
tags:
- Paystubs
properties:
- type: OpenAPI
url: openapi/justworks-paystubs-api-openapi.yml
- type: Documentation
url: https://public-api.justworks.com/v1/docs
- type: JSONSchema
url: json-schema/justworks-payroll-schema.json
- type: JSONSchema
url: json-schema/justworks-paystub-schema.json
- type: JSONSchema
url: json-schema/justworks-time-off-request-schema.json
- aid: justworks:justworks-time-off-balances-api
name: Justworks Time Off Balances API
description: Asynchronous balance reports for time-off policies
humanURL: https://public-api.justworks.com/v1/docs
tags:
- Time Off Balances
properties:
- type: OpenAPI
url: openapi/justworks-time-off-balances-api-openapi.yml
- type: Documentation
url: https://public-api.justworks.com/v1/docs
- type: JSONSchema
url: json-schema/justworks-payroll-schema.json
- type: JSONSchema
url: json-schema/justworks-paystub-schema.json
- type: JSONSchema
url: json-schema/justworks-time-off-request-schema.json
- aid: justworks:justworks-time-off-policies-api
name: Justworks Time Off Policies API
description: Read access to time-off policy catalog
humanURL: https://public-api.justworks.com/v1/docs
tags:
- Time Off Policies
properties:
- type: OpenAPI
url: openapi/justworks-time-off-policies-api-openapi.yml
- type: Documentation
url: https://public-api.justworks.com/v1/docs
- type: JSONSchema
url: json-schema/justworks-payroll-schema.json
- type: JSONSchema
url: json-schema/justworks-paystub-schema.json
- type: JSONSchema
url: json-schema/justworks-time-off-request-schema.json
- aid: justworks:justworks-time-off-requests-api
name: Justworks Time Off Requests API
description: Read access to time-off requests submitted by members
humanURL: https://public-api.justworks.com/v1/docs
tags:
- Time Off Requests
properties:
- type: OpenAPI
url: openapi/justworks-time-off-requests-api-openapi.yml
- type: Documentation
url: https://public-api.justworks.com/v1/docs
- type: JSONSchema
url: json-schema/justworks-payroll-schema.json
- type: JSONSchema
url: json-schema/justworks-paystub-schema.json
- type: JSONSchema
url: json-schema/justworks-time-off-request-schema.json
- aid: justworks:justworks-oauth-api
name: Justworks O Auth API
description: OAuth 2.0 token endpoints
humanURL: https://public-api.justworks.com/v1/docs
tags:
- OAuth
- Authentication
tags_raw:
- OAuth
- Authentication
properties:
- type: OpenAPI
url: openapi/justworks-oauth-api-openapi.yml
- type: Documentation
url: https://public-api.justworks.com/v1/docs
common:
- type: PostmanWorkspace
url: https://www.postman.com/kinlaneapi/justworks/overview
- type: CapabilityMap
url: capabilities/justworks-capability-edges.yml
name: Justworks Business Capability Map
- type: AgenticAccess
url: agentic-access/justworks-agentic-access.yml
- type: VulnerabilityDisclosure
url: security/justworks-vulnerability-disclosure.yml
- type: DomainSecurity
url: security/justworks-domain-security.yml
- type: Authentication
url: authentication/justworks-authentication.yml
- type: OAuthScopes
url: scopes/justworks-scopes.yml
- type: Website
url: https://www.justworks.com
- type: Documentation
url: https://public-api.justworks.com/v1/docs
- type: Portal
url: https://www.justworks.com/partners
- type: GettingStarted
url: https://public-api.justworks.com/v1/docs
- type: Pricing
url: https://www.justworks.com/pricing
- type: Products
url: https://www.justworks.com/products
- type: Integrations
url: https://www.justworks.com/integrations
- type: PartnerProgram
url: https://www.justworks.com/partners
- type: Integrations
url: https://www.justworks.com/partners/integrations
- type: PartnerBlog
url: https://www.justworks.com/partners/blog
- type: HelpCenter
url: https://help.justworks.com
- type: TrustCenter
url: https://trust.justworks.com
- type: Blog
url: https://www.justworks.com/blog
- type: Careers
url: https://www.justworks.com/careers
- type: GitHubOrganization
url: https://github.com/justworkshr
- type: LinkedIn
url: https://www.linkedin.com/company/justworks
- type: Twitter
url: https://twitter.com/JustworksHR
- type: YouTube
url: https://www.youtube.com/c/Justworks
- type: Plans
url: plans/justworks-plans-pricing.yml
- type: RateLimits
url: rate-limits/justworks-rate-limits.yml
- type: FinOps
url: finops/justworks-finops.yml
- type: Features
data:
- Justworks PEO Basic — co-employment PEO with payroll, HR support, and access to large-group benefits
- Justworks PEO Plus — PEO Basic plus medical, dental, vision, life, AD&D, disability, and 401(k) administration
- Justworks Payroll — standalone small-business payroll, time tracking, and HR tooling for companies that source their own
benefits
- Justworks EOR International — employer-of-record service for hiring full-time employees abroad without a local entity
- Justworks Partner API at public-api.justworks.com with OAuth 2.0 authorization-code flow
- Members endpoints (list, get, custom field values, tax-id/SSN) with cursor pagination and updated_at filtering
- Company endpoints (identity, bank account, business info, custom fields, jurisdictions)
- Payroll endpoints (list runs by date range, list fees, list paystubs, get paystub with earnings + deductions + employer
contributions)
- Deductions endpoints (list types, list, create, update, cancel) with per-row operation_id idempotency
- Time Off endpoints (asynchronous balance reports, policies, requests)
- Signed webhooks for member.profile.created/updated, member.employment_state.termination_scheduled/canceled, and department.created/updated/deleted
- Webhook simulator endpoint for partner-listener validation in the Tour environment
- 24-hour access tokens and 30-day refresh tokens
- Hierarchical OAuth scopes (e.g., member.detail:read implies member.basic:read implies member.dob/sex:read)
- Zero-decimal currency representation for all monetary fields
- Partner program with revenue share, co-marketing, dedicated relationship managers
- Integrations marketplace covering Greenhouse, Lever, JazzHR, CultureAmp, 15Five, QuickBooks, NetSuite, Xero, Sage Intacct,
Brex, Ramp
- Available via aggregator platforms Finch, Merge, and Apideck for cross-HRIS access
sources:
- https://public-api.justworks.com/v1/docs
- https://www.justworks.com/pricing
- https://www.justworks.com/integrations
- https://www.justworks.com/partners/integrations
name: Justworks
description: 'Justworks is a New York City-based Professional Employer Organization (PEO) and small-business HR
platform. It bundles payroll, tax filing, multi-state compliance, large-group medical/dental/vision
benefits, 401(k) administration, workers comp, time tracking, and HR consulting into a single
per-employee-per-month subscription. Justworks operates four primary products: Justworks Payroll
(standalone payroll), Justworks PEO Basic, Justworks PEO Plus (PEO with included benefits package),
and Justworks EOR International for hiring full-time employees abroad without a local entity.
Justworks exposes a Partner API at public-api.justworks.com for approved integration partners,
covering Members, Company, Payroll, Paystubs, Deductions, Time Off, and Webhooks. The API uses OAuth
2.0 authorization-code grant, cursor pagination, signed at-least-once webhooks, and zero-decimal
currency representation. Deductions is the primary write surface; everything else is read-only.
'
type: Index
deliveryModel:
model: saas
open_source: false
commercial: true
callable_host: true
label: Hosted service · you call their endpoint
confidence: high
source:
- openapi
- pricing
generated: '2026-08-28'
method: derived
accessModel:
pricing: paid
onboarding: self-serve
trial: false
try_now: false
public: false
gated: none
gated_source:
- onboarding
label: Paid · Self-serve signup
confidence: medium
source:
- plans
- authentication
- security
generated: '2026-11-06'
method: derived
position: Producing
access: 3rd-Party
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/justworks.png
tags:
- PEO
- Payroll
- Human Resources
- Benefits
- Health Insurance
- 401k
- Time Off
- Compliance
- Small Business
- Employer of Record
- HRIS
- Employee Benefits
tags_raw:
- PEO
- Payroll
- HR
- Human Resources
- Benefits
- Health Insurance
- 401(k)
- Time Off
- Compliance
- Small Business
- Employer of Record
- HRIS
- Employee Benefits
maintainers:
- FN: Kin Lane
email: info@apievangelist.com
X: apievangelist
url: https://apievangelist.com
created: '2026-05-25'
modified: '2026-05-25'
specificationVersion: '0.23'
Justworks API — frequently asked questions
Does Justworks have an API?
Yes. APIs.io lists 11 APIs from Justworks, including Justworks Members API, Justworks Company API and Justworks Deductions API, and 8 more.
Is there an OpenAPI specification for the Justworks API?
Yes. APIs.io indexes 11 OpenAPI specifications for Justworks, each linked for download from this page.
How do I authenticate with the Justworks API?
Justworks documents its authentication (oauth2 · 1 scheme). The details are profiled on APIs.io as Justworks Authentication.
How much does the Justworks API cost?
Justworks publishes its prices; its Payroll plan is $8/month/employee + $50/month base fee per employee as of 2026-10-28. APIs.io lists 11 pricing plans for Justworks, with each plan's price, limits and inclusions under Pricing on this page.
Does Justworks have an MCP server?
Yes. APIs.io lists 1 MCP server for Justworks: Remote MCP server at mcp.justworks.com over HTTP.
Is the Justworks API ready for AI agents?
Justworks has a Kin Score of 47.0 out of 100 (developing) and an Agent Readiness score of 41.7 (agent-ready), scored by API Evangelist on 2026-11-06.
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