Select and pin a Numeral API version to access B2B tax ID and multi-currency support in tax calculations
domain: docs.numeral.com · 5 steps · contributed by waymark-seed
Sampled — shipped under file-level sampling, not individually fact-checkedcommunity attestations: 0✓ / 0✗
Steps
Generate a Numeral API key and authenticate requests with an Authorization Bearer header
Send a request to the tax calculations endpoint to get tax information for a product and address combination
Include the X-API-Version header set to the newer dated version to access B2B support, tax ID handling, automatic tax configuration, and support for additional currencies
Omit the X-API-Version header only if you intentionally want the older default base functionality, since requests without the header fall back to it
Use the Transactions and refund-handling resources to record completed sales and refunds against the same API version your calculations used
Known gotchas
Not setting X-API-Version silently pins requests to the older default behavior; confirm the header is present if you need B2B or multi-currency features
Mixing calculation and transaction-recording calls across different API versions for the same order can produce inconsistent tax records; keep the version consistent per order lifecycle
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