OpenAccountants
The only open tax knowledge layer for AI agents where named, licensed accountants stand behind the answers.
Agents can already do the math. None of them can stand behind an answer. Every other tax dataset ships with "not tax advice" and stops there. Here, a named professional with a verified credential reviews the complete Guide for their jurisdiction, publicly, on the record.
The scoreboard
10 of 193 jurisdictions
have a named, licensed Partner on record. The other 183 are open. Claim yours →
Every reviewed Guide carries its reviewer badge — name, credential, review date, public proof:
✅ Accountant-reviewed · Christopher Aryee, CPA (US) · credential verified · 2026-07-04 · 33 corrections, full public diff
1,000+ Guides across 190+ jurisdictions, working with Claude, ChatGPT, Cursor, Windsurf, and any MCP-compatible agent. Every Guide is in exactly one of two states, and the repo greps honestly:
- Source-cited draft — written from primary legislation, every figure cited, not yet professionally reviewed
- Accountant-reviewed — a named, licensed Partner checked the complete Guide; their badge is on it (full roster)
⚠️ General reference only, not advice. Have a qualified professional review outputs before filing, payment, or action. <details><summary>Read the full disclaimer</summary>
</details>OpenAccountants provides general tax and accounting reference material for AI-assisted workflows. It is not a law firm, accounting firm, tax preparer, or return-filing service, and its outputs are not tax, legal, accounting, or financial advice. Guides may be incomplete, outdated, or wrong, and are not reviewed for any specific person's facts, elections, deadlines, residency, or local procedures. Always have a qualified professional review outputs before filing, payment, or action. A source-cited draft has not been reviewed by a credentialed accountant.
What it does
You: "I'm a freelancer in South Africa. What do I owe?"
↓ OA loads za-income-tax, za-provisional-tax
AI: ITR12 working paper
Provisional tax schedule (IRP6, Aug + Feb)
Medical tax credits
Retirement annuity deduction
─────────────────────────────────────────
Reviewed by Werner Britz CA(SA)
[Request accountant review →]Add to your AI → | Browse Guides → | Become a Partner →
Install in 60 seconds
Hosted (1 step, always current): add the OpenAccountants connector to your AI at openaccountants.com/connect, or point any MCP client at:
https://www.openaccountants.com/api/mcpLocal (2 steps, no clone needed): the PyPI package ships with all Guides bundled.
pip install openaccountants-mcp # or: uvx openaccountants-mcp{ "mcpServers": { "openaccountants": { "command": "openaccountants-mcp" } } }Works in Claude Desktop (claude_desktop_config.json), Cursor (.cursor/mcp.json), Claude Code, Windsurf, and any MCP-aware client. Full setup and env vars: mcp/README.md.
Manual (no MCP): download a folder from packages/ and drag the .md files into your AI. Read START-HERE.md for scenarios and what to say.
Partners: the named professionals behind the Guides
The canonical roster lives in PARTNERS.md (and adding yourself to it is step two of Partner onboarding). These licensed practitioners have reviewed Guides for their jurisdictions. Their name appears on every answer the AI gives from a Guide they reviewed, and their reviews are public.
| Jurisdiction | Partner | Guides | Proof |
|---|---|---|---|
| United States (federal forms) | Christopher Aryee, CPA | 4 | 33 OBBBA corrections, full diff |
| United States | Amir Pelinkovic CPA | 16 | profile |
| United Kingdom | James Power | 15 | profile |
| India | Mayur Deokar CA | 13 | profile |
| Indonesia | Rilia Putri CA | 10 | profile |
| Brazil | Ariane Marrocos CRC/SP | 9 | profile |
| Portugal | Mário Vale CA | 9 | profile |
| Saudi Arabia | Mehran Habib | 9 | profile |
| South Africa | Werner Britz CA(SA) | 5 | profile |
| Malta | Michael Cutajar CPA (Malta) | 5 | profile |
| Nepal | Ashish Bista CA | 5 | profile |
| Your jurisdiction | Open (130+ still unclaimed) | — | Become a Partner → |
Accountant-reviewed Guides (Tier 1) are served via the MCP server with the Partner's name on every output. Guides in this repo that no Partner has reviewed yet are source-cited drafts (Tier 2).
Licensed accountant? Review a complete Guide for your jurisdiction and your name goes on it, publicly and permanently. Start here.
Two ways to use
| MCP connector (recommended) | Manual upload from this repo | |
|---|---|---|
| What you get | Accountant-reviewed Guides, the reviewing Partner's name on every answer, AI-to-human handoff (request_accountant_review routes to a real accountant with your worksheet attached) | Source-cited drafts, no reviewer attribution, no handoff |
| How | openaccountants.com/connect, or the install above | Download a folder, drag .md files into your AI |
| Best for | Anyone who wants to actually use OpenAccountants | Developers and accountants who want to audit, fork, or contribute |
| Clients | Claude.ai, ChatGPT (Business+), Cursor, Windsurf, Claude Desktop, Claude Code, any MCP-aware client | Any AI that reads files |
This repo is the public record. Every rate, every review, every correction is auditable here, in the open, with git history. The hosted MCP serves the same content plus the live review layer.
Quick start (manual path)
1. Find your jurisdiction
packages/
├── malta/ ← income tax + VAT + SSC + payroll + formation + bookkeeping
├── uk/ ← SA103/SA100 + VAT100 + NIC + CGT
├── germany/ ← Einkommensteuer + UStVA + payroll (fullest package)
├── brazil/ ← IRPF + PIS/COFINS + e-invoice + payroll
├── south-africa/ ← ITR12 + VAT + provisional tax
├── us-federal/ ← 1040 / 1120 / 1065 / 1041 form guides (CPA-reviewed, OBBBA-current)
├── ... 130+ more countries
├── us-ca/ ← Federal Schedule C/SE + California state
├── ... 51 US state packages
├── ca-on/ ← Federal T1/T2125 + Ontario
├── ... 13 Canadian province/territory packagesNew here? Read START-HERE.md: scenarios, file lists, what to say to the AI. The full machine-readable inventory of every Guide is index.json.
2. Upload to your AI
- Claude.ai → Create a Project, add files as Project Knowledge
- ChatGPT → Attach files or create a Custom GPT
- Any other AI → Attach or paste the files
3. Go
Help me with my 2025 taxes. Here's my bank statement.
Help me set up a company in Malta.
Run my payroll for this month.
Prepare my annual accounts.
Optimize my tax. What deductions am I missing?
Check my invoice compliance for EU e-invoicing.The AI asks a few questions, loads the right Guides, and produces a working paper for your accountant.
What's in each package
| File | What it does |
|---|---|
foundation.md | Tells the AI how to work: conservative defaults, output format, classification rules |
intake.md | Onboarding questions, refusal checks, document inference |
[country]-income-tax.md | Income tax brackets, deductions, transaction patterns |
[country]-vat.md | VAT/GST/sales tax rules, supplier patterns, form mappings |
[country]-ssc.md | Social security / pension contributions |
[country]-payroll.md | PAYE withholding, employer filing (15 countries) |
[country]-formation.md | Entity types, registration, costs (13 countries) |
[country]-bookkeeping.md | Chart of accounts, P&L, balance sheet (13 countries) |
[country]-financial-statements.md | Annual accounts, reporting framework (13 countries) |
[country]-transfer-pricing.md | TP documentation, arm's length, CbCR (15 countries) |
[country]-tax-optimization.md | Legal deductions, timing strategies (14 countries) |
[country]-crypto-tax.md | CGT on crypto, DeFi, staking, NFTs (22 countries + all US states) |
[country]-guided-intake.md | Full guided experience (13 countries) |
[country]-return-assembly.md | Cross-checks: VAT × IT × SSC (13 countries) |
Special packages: _cross-border/ (37 skills) · _verticals/ (14 industry skills) · _integrations/ (10 platform skills: Xero, QuickBooks, Stripe, Wise, Shopify, and more) · us-federal/ (US federal form guides + machine-readable rates.2025.json / rates.2026.json) · uk/ (structured rates.2025.json, 2025/26, every figure statute-cited)
Coverage
Full accounting suite (13 countries)
Tax + bookkeeping + payroll + formation + financial statements + transfer pricing + tax optimization:
Malta · UK · Germany · Australia · Canada · India · Spain · France · Japan · Netherlands · Portugal · Belgium · United States (CA)
Multi-skill countries (~56 countries)
VAT + income tax + social contributions (and often more):
Argentina, Austria, Belgium, Brazil, Bulgaria, Chile, China, Colombia, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Greece, Hong Kong, Hungary, Indonesia, Ireland, Israel, Kenya, Latvia, Lithuania, Luxembourg, Malaysia, Mexico, New Zealand, Nigeria, Norway, Pakistan, Panama, Peru, Philippines, Poland, Qatar, Romania, Saudi Arabia, Singapore, Slovakia, Slovenia, South Africa, South Korea, Sweden, Switzerland, Taiwan, UAE, and more.
Crypto tax (22 countries + all 51 US states)
Malta, UK, Germany, France, Australia, Canada, Israel, India, Japan, Spain, Netherlands, Portugal, Italy, Singapore, Brazil, Mexico, Sweden, Belgium, Switzerland, South Korea, New Zealand, and every us-<state> package.
VAT/GST only (65 countries)
Consumption tax classification with local supplier pattern libraries. From Albania to Zimbabwe.
Full coverage breakdown: [docs/QUALITY-TIERS.md](do
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