Supported jurisdictions

The default geo profiles and regime registry model 52 countries. A usable assessment also requires the relevant register data and enough information about the seller, customer and supply. A rate existing in the register does not by itself add a country to the engine's regime registry.

Modelled regimes

Countries	Engine module	Calculation path
AT BE BG HR CY CZ DK EE FI FR DE GR HU IE IT LV LT LU MT NL PL PT RO SK SI ES SE	`eu-vat`	EU place of supply, B2B reverse charge and the scoped micro-business threshold
GB CH NO AU NZ MX SG TW AE SA BH OM TR CL ID VN PH JP KR TH UA	National VAT/GST modules	`NationalTaxRegime`, including its cross-border B2B treatment
IN	`in-gst`	India GST with IGST or CGST/SGST component labels
MY	`my-sst`	Malaysia service tax without the generic VAT reverse-charge treatment
US	`us-sales-tax`	Registration, marketplace, taxability, sourcing and local-authority gates
CA	`ca-gst`	Federal GST plus the province's PST/QST or a harmonised HST; PST needs the province's own permit

Outside the United States, collection is gated on the seller's registrations: a supply into a country where the seller is neither established nor registered comes back NotRegistered rather than charged. See seller registrations.

See Regimes for the rules each implementation models and Unsupported jurisdictions for the remaining boundary.

Rates and confidence

Every default rate comes from RegisterRateSource. Run tax:data:sync before pricing. The register supplies dated standard, reduced and zero rates; there is no bundled national snapshot or illustrative province-rate fallback.

A commodity code can refine a category lookup. If several applicable rates remain ambiguous, the source uses the standard rate with RateLimit::HeadingAmbiguous. Conditions that narrow an inherited category answer are reported with RateLimit::ConditionsUnevaluated, and a category where the law names a rate the register declined to file — Burkina Faso's 10% for approved hotels — with RateLimit::RateDeclined. A place whose marketplace mandate reaches only some facilitated sales leaves the seller charging, with RateLimit::MarketplaceLiabilityUnread. Read confidence, limitedBy and provenance on the returned rate rather than treating an entire country's coverage as one confidence grade. See Rate sources.

Rates are resolved against the supply date where the register carries that window. A missing historical rate does not become today's rate. Source monitoring and data publication belong to the register; the package updates its local copy through sync.

US address precision

The available paths are described in register coverage: ZIP+4, optional street indexes, polygons and county names. Postal and polygon artifacts are included in sync by default; street indexes are selected with --streets=KS,WA. Enable tax.geocodio.rooftop to have the shipped geocoder attach ZIP+4 or point localities. County resolution works without that option.

Where the applicable local authorities cannot be resolved, a state share can be returned as Derived with NoLocalResolution. It must not be treated as a complete address-level rate. SaaS taxability and nexus thresholds describe two separate inputs to the US regime.

Tax-ID validation

VIES, HMRC and optional ABN Lookup validators are separate from the register. An unavailable validation service returns an inconclusive result. Store the actual validation result when relying on it for the customer treatment.