Get Tax Categories

Returns tax category code enumeration per OMN Tax Authority VAT Law requirements. Each category includes the code identifier, description, and default tax rate percentage. Used for ClassifiedTaxCategory/ID (IBT-151) on document lines and for tax_category on charges and allowances.

Usage in document payloads

Set classified_tax_category.id to a plain string (S, E, O, or Z) — not an object with code/desc.

Standard rate (`S`)

"classified_tax_category": {
  "id": "S",
  "percent": 5.0,
  "tax_scheme": "VAT"
}

Exempt (`E`)

Include exemption reason fields (see Tax Exemption Reason Codes):

"classified_tax_category": {
  "id": "E",
  "percent": 0.0,
  "tax_scheme": "VAT",
  "tax_exemption_reason_code": "VATEX-OM-01",
  "tax_exemption_reason": "Qualifying Financial Services"
}

Out of scope (`O`)

"classified_tax_category": {
  "id": "O",
  "percent": 0.0,
  "tax_scheme": "VAT"
}

Zero rated (`Z`)

Include zero-rated reason fields:

"classified_tax_category": {
  "id": "Z",
  "percent": 0.0,
  "tax_scheme": "VAT",
  "zero_rated_reason_code": "VATZR-OM-01",
  "zero_rated_reason": "Qualifying Supply of Food items specified by a decision from the Chairman"
}

Categories

• S (Standard rate): Standard VAT rate of 5% — used for most goods and services

• E (Exempt): Exempt from VAT — requires tax_exemption_reason_code and tax_exemption_reason

• O (Out of scope): Not subject to VAT

• Z (Zero rated): Zero-rated VAT — requires zero_rated_reason_code and zero_rated_reason

Use these codes on document lines for:

• Sale invoices

• Sale credit notes

• Purchase invoices

• Purchase credit notes

See the right panel for request, response, and JSON examples.