Column Tax website screenshot

Column Tax

Column Tax is an IRS-authorized, API-first tax filing platform that lets banks, brokerages, neobanks, and SMB/freelancer fintech apps embed a full white-label income-tax preparation and e-file experience directly inside their own product. Partners create a Column Tax user via a server-side REST call, receive a short-lived authenticated URL, and launch the Column Tax UI (web loader or native iOS, Android, and React Native SDKs) embedded in their app, while webhooks report each user through the filing lifecycle. Column Tax offers DIY Filing and Expert Review products, is a SOC 2-certified and IRS-authorized e-file provider, and reports outcomes such as higher retention and direct-deposit switching for embedded partners.

Column Tax publishes 1 API on the APIs.io network. Tagged areas include Company, Fintech, Tax, Tax Filing, and Embedded Finance.

The Column Tax catalog on APIs.io includes 1 event-driven AsyncAPI specification.

Column Tax’s developer surface includes documentation, API reference, getting-started guide, quickstart, authentication, support, engineering blog, and 21 more developer resources.

🌐 Visit website 📡 Source on GitHub
43.1/100 thin ▬ flat Agent 35/100 agent aware Full breakdown ↓
scored 2026-07-27 · rubric v0.5
AccessSelf serve
1 APIs 1 MCP Servers
CompanyFintechTaxTax FilingEmbedded FinanceE-FileFinancial ServicesBankingAPI First

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-07-27 · rubric v0.5
Composite quality — 43.1/100 · thin
Contract Quality 5.7 / 25
Developer Ergonomics 14.8 / 20
Commercial Clarity 5.8 / 20
Operational Transparency 3.8 / 13
Governance 0.0 / 12
Discoverability 9.3 / 10
Agent readiness — 35/100 · agent aware
Machine-Readable Contract 0 / 18
Agentic Access Contract 0 / 15
MCP Server 12 / 12
Machine-Readable Auth 10 / 10
Idempotency 0 / 9
Stable Error Semantics 8 / 8
Request/Response Examples 0 / 7
Rate-Limit Signaling 0 / 7
Typed Event Surface 6 / 6
Agent Skills 0 / 5
Well-Known Catalog 0 / 4
Consent & Bot Identity 0 / 3
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/column-tax: 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 1

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

Column Tax API

REST API to embed IRS-authorized income-tax preparation and e-filing. Create a Column Tax user, obtain a short-lived authenticated URL to launch the embedded filing UI, list a u...

MCP Servers 1

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

column-tax-mcp.yml

MCP SERVER

Event Specifications 1

AsyncAPI definitions for this provider's event-driven and streaming APIs.

Column Tax Webhooks

ASYNCAPI

Security Posture 2

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Column Tax Authentication

http · 1 scheme

SECURITY

Column Tax Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Resources

Get Started 4

Portal, sign-up, and the first successful call

DeveloperPortal
DeveloperPortal
 GettingStarted
GettingStarted
 Quickstart
Quickstart
 Sandbox
Sandbox

Documentation 2

Reference material describing how the API behaves

Documentation
Documentation
 APIReference
APIReference

Agent Surfaces 2

MCP servers, agent skills, and machine-readable catalogs

LLMsTxt
LLMsTxt
 MCPServer
MCPServer

Design & Contract 7

Pagination, idempotency, versioning, errors, and events

Conventions
Conventions
 ErrorCatalog
ErrorCatalog
 Lifecycle
Lifecycle
 Conformance
Conformance
 Webhooks
Webhooks
 DataModel
DataModel
 Components
Components

Scroll for all 7

Build 3

SDKs, sample code, and the tooling you integrate with

GitHubOrganization
GitHubOrganization
 Packages
Packages
 SDKs
SDKs

Access & Security 4

Authentication, authorization, and security posture

DomainSecurity
DomainSecurity
 Authentication
Authentication
 Authentication
Authentication
 Compliance
Compliance

Operate 2

Status, limits, changes, and where to get help

Support
Support
 StatusPage
StatusPage

Commercial 2

Pricing, plans, and the legal terms of use

TermsOfService
TermsOfService
 PrivacyPolicy
PrivacyPolicy

Company 2

The organization behind the API

Website
Website
 Blog
Blog

Source (apis.yml)

apis.yml Raw ↑ 
aid: column-tax
name: Column Tax
description: Column Tax is an IRS-authorized, API-first tax filing platform that lets banks, brokerages, neobanks, and SMB/freelancer
  fintech apps embed a full white-label income-tax preparation and e-file experience directly inside their own product. Partners
  create a Column Tax user via a server-side REST call, receive a short-lived authenticated URL, and launch the Column Tax
  UI (web loader or native iOS, Android, and React Native SDKs) embedded in their app, while webhooks report each user through
  the filing lifecycle. Column Tax offers DIY Filing and Expert Review products, is a SOC 2-certified and IRS-authorized e-file
  provider, and reports outcomes such as higher retention and direct-deposit switching for embedded partners.
url: https://raw.githubusercontent.com/api-evangelist/column-tax/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://cdn.prod.website-files.com/6262ffa3aeadc15ee876298b/627bf917c708fc0ec6460fcb_Text_Image.png
x-type: company
x-source: vc-portfolio
x-backed-by:
- bain-capital-ventures
x-tier: stub
x-tier-reason: portfolio-lead
specificationVersion: '0.20'
created: '2026-07-17'
modified: '2026-07-18'
tags:
- Company
- Fintech
- Tax
- Tax Filing
- Embedded Finance
- E-File
- Financial Services
- Banking
- API First
apis:
- name: Column Tax API
  description: REST API to embed IRS-authorized income-tax preparation and e-filing. Create a Column Tax user, obtain a short-lived
    authenticated URL to launch the embedded filing UI, list a user's tax returns and jurisdictions, and subscribe to webhook
    events across the filing lifecycle.
  humanURL: https://docs.columntax.com/v1.1/reference
  baseURL: https://prod.columnapi.com
  tags:
  - Tax
  - E-File
  - Embedded Finance
  properties:
  - type: Documentation
    url: https://docs.columntax.com/docs/welcome
  - type: APIReference
    url: https://docs.columntax.com/v1.1/reference
  - type: Authentication
    url: https://docs.columntax.com/reference/authentication
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: DomainSecurity
  url: security/column-tax-domain-security.yml
- type: Website
  url: https://www.columntax.com/
- type: DeveloperPortal
  url: https://docs.columntax.com/docs/welcome
- type: Documentation
  url: https://docs.columntax.com/docs/welcome
- type: APIReference
  url: https://docs.columntax.com/v1.1/reference
- type: GettingStarted
  url: https://docs.columntax.com/docs/quick-start
- type: Quickstart
  url: https://docs.columntax.com/docs/quick-start
- type: Authentication
  url: https://docs.columntax.com/reference/authentication
- type: Support
  url: https://www.columntax.com/contact-us
- type: Blog
  url: https://www.columntax.com/blog
- type: GitHubOrganization
  url: https://github.com/column-tax
- type: StatusPage
  url: https://status.columntax.com
- type: TermsOfService
  url: https://www.columntax.com/terms-of-use
- type: PrivacyPolicy
  url: https://www.columntax.com/privacy-policy
- type: Packages
  url: packages/column-tax-packages.yml
- type: SDKs
  url: packages/column-tax-packages.yml
- type: LLMsTxt
  url: llms/column-tax-llms.txt
- type: Authentication
  url: authentication/column-tax-authentication.yml
- type: Conventions
  url: conventions/column-tax-conventions.yml
- type: ErrorCatalog
  url: errors/column-tax-problem-types.yml
- type: Lifecycle
  url: lifecycle/column-tax-lifecycle.yml
- type: Conformance
  url: conformance/column-tax-conformance.yml
- type: Compliance
  url: conformance/column-tax-conformance.yml
- type: MCPServer
  url: mcp/column-tax-mcp.yml
- type: Sandbox
  url: sandbox/column-tax-sandbox.yml
- type: Webhooks
  url: asyncapi/column-tax-webhooks.yml
- type: DataModel
  url: data-model/column-tax-data-model.yml
- type: Components
  url: components/column-tax-components.yml
x-enrichment:
  date: '2026-07-19'
  status: backfilled
  pass: local-v1
  note: backfilled from .gitignore signal + verified work evidence