Treaty Rate API

Coming Q3 2026

Programmatic access to 902 treaty pairs across 50 country networks. Every rate traced to official government sources, with structured metadata on treaty status, qualification thresholds, and source authority.

Example Request

HTTPGET

GET /api/v1/rates?from=US&to=GB&type=dividends

Example Response

JSON200 OK

{
  "from": "US",
  "to": "GB",
  "income_type": "dividends",
  "treaty_status": "in_force",
  "rates": {
    "general": 15,
    "qualified": 0,
    "qualified_threshold": "80% voting power, pension fund, or government"
  },
  "statutory_rate": 30,
  "savings": 15,
  "source": {
    "authority": "IRS Table 1 (Rev. May 2023)",
    "url": "https://www.irs.gov/pub/irs-utl/Tax_Treaty_Table_1_2023_Feb.pdf",
    "last_verified": "2026-03-15"
  },
  "treaty": {
    "signed": "2001-07-24",
    "in_force": "2003-03-31",
    "slug": "us-united-kingdom"
  }
}

What the API Returns

Treaty withholding ratesGeneral and qualified rates for dividends, interest, royalties, pensions, and social security

Statutory comparisonDomestic statutory rate alongside treaty rate, with computed savings

Source provenanceOfficial authority name, URL, and last-verified date for every rate

Treaty metadataSigned date, entry-into-force date, suspension status, and applicable protocols

Qualification thresholdsOwnership percentages and conditions required for reduced rates

Use Cases

Tax Software

Embed real-time treaty rates in tax preparation and compliance software. Eliminate manual lookups and reduce filing errors.

Payroll Platforms

Automate withholding calculations for international employees and contractors. Apply the correct treaty rate at the point of payment.

Financial Analytics

Model after-tax returns on cross-border investments. Compare treaty networks to optimize holding structures and dividend flows.

Wealth Management

Look up treaty benefits for clients with international income — dividends, interest, pensions, and royalties across all 902 treaty pairs.

Enterprise Access

The API is designed for production integration. Pricing is based on volume and use case. Contact us to discuss your requirements and join the early access list.

api@taxinpangea.com

Note: The API returns treaty rates as published by official sources. Rates are subject to Limitation on Benefits (LOB) and Principal Purpose Test (PPT) provisions. The API does not constitute tax advice. Consult a qualified tax professional for guidance specific to your situation.