Finix Payments

Finix is a full-stack payments technology provider that lets businesses, software platforms, and marketplaces accept and send payments online and in person. Its REST API (version 2022-02-01) covers the full payments lifecycle — Identities, Merchants, Payment Instruments, Authorizations, Transfers, Settlements, Disputes, Verifications, Fee/Payout Profiles, Devices/terminals, and Webhooks — enabling card, ACH, EFT, digital-wallet, and Buy-Now-Pay-Later acceptance, seller onboarding/underwriting, split transfers, payouts, and payment facilitation (PayFac-as-a-service). Finix is a Level 1 PCI DSS certified platform with browser (finix.js) and mobile tokenization SDKs, hosted checkout pages, and payment links. Authentication is HTTP Basic Auth with environment-scoped API keys; the API uses cursor pagination, idempotency_id request-level idempotency, HAL responses, and dated versioning via the Finix-Version header.

Finix Payments publishes 19 APIs on the APIs.io network, including Authorizations API, Balance Transfers API, Compliance Forms API, and 16 more. Tagged areas include Company, Payments, Payment Processing, Payment Facilitation, and Embedded Finance.

The Finix Payments catalog on APIs.io includes 1 event-driven AsyncAPI specification.

Finix Payments’ developer surface includes documentation, API reference, getting-started guide, support, engineering blog, pricing, signup flow, and 31 more developer resources.

🌐 Visit website 📡 Source on GitHub

64.7/100 strong ▬ flat Agent 51/100 agent native Full breakdown ↓
scored 2026-08-10 · rubric v0.9.1

AccessSelf serve

19 APIs 1 MCP Servers

CompanyPaymentsPayment ProcessingPayment FacilitationEmbedded FinanceMarketplacesACHCard AcceptanceFintechPCI DSS

Kin Score

Kin Score How this is scored →
scored 2026-08-10 · rubric v0.9.1

Composite quality — 64.7/100 · strong

Contract Quality 17.5 / 25

Developer Ergonomics 14.7 / 20

Commercial Clarity 10.5 / 20

Operational Transparency 9.6 / 13

Governance 2.5 / 12

Discoverability 9.3 / 10

Agent readiness — 51/100 · agent native

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

MCP Server 12 / 12

Machine-Readable Auth 10 / 10

Idempotency 9 / 9

Stable Error Semantics 8 / 8

Request/Response Examples 7 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 6 / 6

Agent Skills 5 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/finix-payments: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

APIs 19

Individual APIs this provider publishes, each with its own machine-readable definition.

MCP Servers 1

Model Context Protocol servers that expose these APIs to AI agents.

finix-payments-mcp.yml

MCP SERVER

Rate Limits 1

Documented rate limits and quota policies.

Get Started 4

Portal, sign-up, and the first successful call

DeveloperPortal

GettingStarted

SignUp

Sandbox

Documentation 2

Reference material describing how the API behaves

Documentation

Documentation

APIReference

APIReference

Agent Surfaces 4

MCP servers, agent skills, and machine-readable catalogs

MCPServer

AgentSkill

AgenticAccess

LLMsTxt

Design & Contract 10

Pagination, idempotency, versioning, errors, and events

Conventions

Idempotency

ErrorCatalog

Lifecycle

Components

DataModel

Conformance

Webhooks

Arazzo

Arazzo

Scroll for all 10

Build 5

SDKs, sample code, and the tooling you integrate with

PostmanWorkspace

PostmanWorkspace

GitHubOrganization

Packages

SDKs

DeclineCodes

Access & Security 3

Authentication, authorization, and security posture

Authentication

Authentication

Compliance

Compliance

DomainSecurity

DomainSecurity

Operate 5

Status, limits, changes, and where to get help

Support

StatusPage

RateLimits

Deprecation

ChangeLog

Commercial 3

Pricing, plans, and the legal terms of use

Pricing

Pricing

TermsOfService

TermsOfService

PrivacyPolicy

PrivacyPolicy

Company 2

The organization behind the API

Website

Website

Blog

Blog

Source (apis.yml)

aid: finix-payments
name: Finix Payments
description: Finix is a full-stack payments technology provider that lets businesses, software platforms, and marketplaces
  accept and send payments online and in person. Its REST API (version 2022-02-01) covers the full payments lifecycle — Identities,
  Merchants, Payment Instruments, Authorizations, Transfers, Settlements, Disputes, Verifications, Fee/Payout Profiles, Devices/terminals,
  and Webhooks — enabling card, ACH, EFT, digital-wallet, and Buy-Now-Pay-Later acceptance, seller onboarding/underwriting,
  split transfers, payouts, and payment facilitation (PayFac-as-a-service). Finix is a Level 1 PCI DSS certified platform
  with browser (finix.js) and mobile tokenization SDKs, hosted checkout pages, and payment links. Authentication is HTTP Basic
  Auth with environment-scoped API keys; the API uses cursor pagination, idempotency_id request-level idempotency, HAL responses,
  and dated versioning via the Finix-Version header.
url: https://raw.githubusercontent.com/api-evangelist/finix-payments/refs/heads/main/apis.yml
accessModel:
  pricing: unknown
  onboarding: self-serve
  trial: false
  try_now: false
  public: false
  label: Self-serve signup
  confidence: medium
  source:
  - authentication
  generated: '2026-07-22'
  method: derived
image: https://images.ctfassets.net/kqru4vgwujx6/3dBfyfPS31FWqFPTwf4dRv/417cc8b5e94029726cffb9aa85230111/OG_Image.png?w=1200&q=90
x-type: company
x-source: vc-portfolio
x-backed-by:
- insight-partners
x-tier: enriched
x-tier-reason: openapi-and-docs-harvested
specificationVersion: '0.20'
created: '2026-07-17'
modified: '2026-07-19'
tags:
- Company
- Payments
- Payment Processing
- Payment Facilitation
- Embedded Finance
- Marketplaces
- ACH
- Card Acceptance
- Fintech
- PCI DSS
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
apis:
- aid: finix-payments:finix-payments-authorizations-api
  name: Finix Payments Authorizations API
  description: '{''$ref'': ''api-descriptions/tags/authorizations.md''}'
  humanURL: https://finix.com/docs/api
  baseURL: https://finix.live-payments-api.com
  tags:
  - Authorizations
  properties:
  - type: OpenAPI
    url: openapi/finix-payments-authorizations-api-openapi.yml
- aid: finix-payments:finix-payments-balance-transfers-api
  name: Finix Payments Balance Transfers API
  description: '{''$ref'': ''api-descriptions/tags/balance-transfers.md''}'
  humanURL: https://finix.com/docs/api
  baseURL: https://finix.live-payments-api.com
  tags:
  - Balance Transfers
  properties:
  - type: OpenAPI
    url: openapi/finix-payments-balance-transfers-api-openapi.yml
- aid: finix-payments:finix-payments-compliance-forms-api
  name: Finix Payments Compliance Forms API
  description: '{''$ref'': ''api-descriptions/tags/compliance-forms.md''}'
  humanURL: https://finix.com/docs/api
  baseURL: https://finix.live-payments-api.com
  tags:
  - Compliance Forms
  properties:
  - type: OpenAPI
    url: openapi/finix-payments-compliance-forms-api-openapi.yml
- aid: finix-payments:finix-payments-devices-api
  name: Finix Payments Devices API
  description: '{''$ref'': ''api-descriptions/tags/devices.md''}'
  humanURL: https://finix.com/docs/api
  baseURL: https://finix.live-payments-api.com
  tags:
  - Devices
  properties:
  - type: OpenAPI
    url: openapi/finix-payments-devices-api-openapi.yml
- aid: finix-payments:finix-payments-disputes-api
  name: Finix Payments Disputes API
  description: '{''$ref'': ''api-descriptions/tags/disputes.md''}'
  humanURL: https://finix.com/docs/api
  baseURL: https://finix.live-payments-api.com
  tags:
  - Disputes
  properties:
  - type: OpenAPI
    url: openapi/finix-payments-disputes-api-openapi.yml
- aid: finix-payments:finix-payments-fee-profiles-api
  name: Finix Payments Fee Profiles API
  description: '{''$ref'': ''api-descriptions/tags/fee-profiles.md''}'
  humanURL: https://finix.com/docs/api
  baseURL: https://finix.live-payments-api.com
  tags:
  - Fee Profiles
  properties:
  - type: OpenAPI
    url: openapi/finix-payments-fee-profiles-api-openapi.yml
- aid: finix-payments:finix-payments-files-api
  name: Finix Payments Files API
  description: '{''$ref'': ''api-descriptions/tags/files.md''}'
  humanURL: https://finix.com/docs/api
  baseURL: https://finix.live-payments-api.com
  tags:
  - Files
  properties:
  - type: OpenAPI
    url: openapi/finix-payments-files-api-openapi.yml
- aid: finix-payments:finix-payments-identities-api
  name: Finix Payments Identities API
  description: '{''$ref'': ''api-descriptions/tags/identities.md''}'
  humanURL: https://finix.com/docs/api
  baseURL: https://finix.live-payments-api.com
  tags:
  - Identities
  properties:
  - type: OpenAPI
    url: openapi/finix-payments-identities-api-openapi.yml
- aid: finix-payments:finix-payments-instrument-updates-api
  name: Finix Payments Instrument Updates API
  description: '{''$ref'': ''api-descriptions/tags/instrument-updates.md''}'
  humanURL: https://finix.com/docs/api
  baseURL: https://finix.live-payments-api.com
  tags:
  - Instrument Updates
  properties:
  - type: OpenAPI
    url: openapi/finix-payments-instrument-updates-api-openapi.yml
- aid: finix-payments:finix-payments-merchant-profiles-api
  name: Finix Payments Merchant Profiles API
  description: '{''$ref'': ''api-descriptions/tags/merchant-profiles.md''}'
  humanURL: https://finix.com/docs/api
  baseURL: https://finix.live-payments-api.com
  tags:
  - Merchant Profiles
  properties:
  - type: OpenAPI
    url: openapi/finix-payments-merchant-profiles-api-openapi.yml
- aid: finix-payments:finix-payments-merchants-api
  name: Finix Payments Merchants API
  description: '{''$ref'': ''api-descriptions/tags/merchants.md''}'
  humanURL: https://finix.com/docs/api
  baseURL: https://finix.live-payments-api.com
  tags:
  - Merchants
  properties:
  - type: OpenAPI
    url: openapi/finix-payments-merchants-api-openapi.yml
- aid: finix-payments:finix-payments-onboarding-forms-api
  name: Finix Payments Onboarding Forms API
  description: '{''$ref'': ''api-descriptions/tags/onboarding-forms.md''}'
  humanURL: https://finix.com/docs/api
  baseURL: https://finix.live-payments-api.com
  tags:
  - Onboarding Forms
  properties:
  - type: OpenAPI
    url: openapi/finix-payments-onboarding-forms-api-openapi.yml
- aid: finix-payments:finix-payments-payment-instruments-api
  name: Finix Payments Payment Instruments API
  description: '{''$ref'': ''api-descriptions/tags/payment-instruments.md''}'
  humanURL: https://finix.com/docs/api
  baseURL: https://finix.live-payments-api.com
  tags:
  - Payment Instruments
  properties:
  - type: OpenAPI
    url: openapi/finix-payments-payment-instruments-api-openapi.yml
- aid: finix-payments:finix-payments-payout-profiles-api
  name: Finix Payments Payout Profiles API
  description: '{''$ref'': ''api-descriptions/tags/payout-profiles.md''}'
  humanURL: https://finix.com/docs/api
  baseURL: https://finix.live-payments-api.com
  tags:
  - Payout Profiles
  properties:
  - type: OpenAPI
    url: openapi/finix-payments-payout-profiles-api-openapi.yml
- aid: finix-payments:finix-payments-settlements-api
  name: Finix Payments Settlements API
  description: '{''$ref'': ''api-descriptions/tags/settlements.md''}'
  humanURL: https://finix.com/docs/api
  baseURL: https://finix.live-payments-api.com
  tags:
  - Settlements
  properties:
  - type: OpenAPI
    url: openapi/finix-payments-settlements-api-openapi.yml
- aid: finix-payments:finix-payments-split-transfers-api
  name: Finix Payments Split Transfers API
  description: '{''$ref'': ''api-descriptions/tags/split-transfers.md''}'
  humanURL: https://finix.com/docs/api
  baseURL: https://finix.live-payments-api.com
  tags:
  - Split Transfers
  properties:
  - type: OpenAPI
    url: openapi/finix-payments-split-transfers-api-openapi.yml
- aid: finix-payments:finix-payments-transfers-api
  name: Finix Payments Transfers API
  description: '{''$ref'': ''api-descriptions/tags/transfers.md''}'
  humanURL: https://finix.com/docs/api
  baseURL: https://finix.live-payments-api.com
  tags:
  - Transfers
  properties:
  - type: OpenAPI
    url: openapi/finix-payments-transfers-api-openapi.yml
- aid: finix-payments:finix-payments-verifications-api
  name: Finix Payments Verifications API
  description: '{''$ref'': ''api-descriptions/tags/verifications.md''}'
  humanURL: https://finix.com/docs/api
  baseURL: https://finix.live-payments-api.com
  tags:
  - Verifications
  properties:
  - type: OpenAPI
    url: openapi/finix-payments-verifications-api-openapi.yml
- aid: finix-payments:finix-payments-webhooks-api
  name: Finix Payments Webhooks API
  description: '{''$ref'': ''api-descriptions/tags/webhooks.md''}'
  humanURL: https://finix.com/docs/api
  baseURL: https://finix.live-payments-api.com
  tags:
  - Webhooks
  properties:
  - type: OpenAPI
    url: openapi/finix-payments-webhooks-api-openapi.yml
common:
- type: PostmanWorkspace
  url: https://www.postman.com/kinlaneapi/finix-payments/overview
- type: Website
  url: https://www.finixpayments.com/
- type: DeveloperPortal
  url: https://docs.finix.com/
- type: Documentation
  url: https://docs.finix.com/
- type: APIReference
  url: https://finix.com/docs/api
- type: GettingStarted
  url: https://docs.finix.com/guides/getting-started
- type: Support
  url: https://docs.finix.com/guides/getting-started/support-at-finix
- type: Blog
  url: https://finix.com/resources/blogs
- type: GitHubOrganization
  url: https://github.com/finix-payments
- type: Pricing
  url: https://finix.com/pricing
- type: SignUp
  url: https://dashboard.finixpayments.com
- type: TermsOfService
  url: https://finix.com/terms-and-policies
- type: PrivacyPolicy
  url: https://finix.com/terms-and-policies
- type: StatusPage
  url: https://status.finix.com
- type: Packages
  url: packages/finix-payments-packages.yml
- type: SDKs
  url: packages/finix-payments-packages.yml
- type: Authentication
  url: authentication/finix-payments-authentication.yml
- type: Conventions
  url: conventions/finix-payments-conventions.yml
- type: Idempotency
  url: conventions/finix-payments-conventions.yml
- type: RateLimits
  url: rate-limits/finix-payments-rate-limits.yml
- type: ErrorCatalog
  url: errors/finix-payments-problem-types.yml
- type: DeclineCodes
  url: errors/finix-payments-decline-codes.yml
- type: Lifecycle
  url: lifecycle/finix-payments-lifecycle.yml
- type: Deprecation
  url: https://docs.finix.com/additional-resources/developers/authentication-and-api-basics/versioning
- type: ChangeLog
  url: changelog/finix-payments-changelog.yml
- type: Sandbox
  url: sandbox/finix-payments-sandbox.yml
- type: Components
  url: components/finix-payments-components.yml
- type: DataModel
  url: data-model/finix-payments-data-model.yml
- type: Conformance
  url: conformance/finix-payments-conformance.yml
- type: Compliance
  url: conformance/finix-payments-conformance.yml
- type: Webhooks
  url: asyncapi/finix-payments-webhooks.yml
- type: MCPServer
  url: mcp/finix-payments-mcp.yml
- type: AgentSkill
  url: skills/_index.yml
- type: AgenticAccess
  url: agentic-access/finix-payments-agentic-access.yml
- type: LLMsTxt
  url: llms/finix-payments-llms.txt
- type: DomainSecurity
  url: security/finix-payments-domain-security.yml
- type: Arazzo
  name: Accept a card payment (auth + capture)
  url: arazzo/finix-payments-accept-a-card-payment.yml
- type: Arazzo
  name: Onboard a seller/merchant
  url: arazzo/finix-payments-onboard-a-merchant.yml
x-enrichment:
  date: '2026-07-19'
  status: backfilled
  pass: local-v1
  note: backfilled from .gitignore signal + verified work evidence