Zamp API

Name: Zamp Sales Tax Management Service
Brand: Zamp

Calculate sales tax accurately, sync transactions, and automate compliance across your systems.

Integration overview.

Real-time and rooftop accurate tax calculations

Transaction syncing and historical backfills.

Nexus tracking and multi-state compliance.

Why Zamp for API integrations.

Accuracy that holds up beyond calculation

Jurisdiction-level tax calculations and data that remain reliable through reporting, reconciliation, and filings.

Clear, production-ready documentation.

API docs built to get teams live quickly and stay useful as systems evolve.

Dedicated technical support.

Work directly with a dedicated tax engineer who understands your integration and compliance needs.

Access to the full Zamp compliance platform.

The API connects directly to registrations, filings, and ongoing compliance workflows, not just calculations.

Everything you need for global sales tax — in one place.

Get started

4 simple steps to integrate with the Zamp API.

Generate API credentials.

Create an API token and securely configure access.

Configure nexus and tax settings.

Define nexus and product taxability to match your business with support from your dedicated onboarding team.

Send transactions.

Calculate tax in real time at checkout or sync completed transactions in batches.

Monitor, audit, and scale.

Access detailed logs, transaction histories, and calculation outputs. No manual action required unless review is needed.

FAQs.

Still have questions? Call us at 1-866-438-9267 or email us at support@zamp.com.

Can teams start with calculations and add compliance later?

Yes. Many teams begin by using the API for tax calculations and transaction syncing, then extend into registrations, filings, and managed compliance as their needs evolve.

Can the API support multiple legal entities?

Yes. The Zamp API supports multiple legal entities and EINs within a single account, making it suitable for multi-entity and complex organizational structures.

Does the API support historical transactions?

Yes. The API supports syncing historical transactions by date range, allowing teams to backfill prior activity for accurate reporting, reconciliation, and filings.

How are API requests authenticated?

Zamp uses bearer token authentication. All API requests must include a valid token in the HTTP Authorization header.

How does the API handle refunds and adjustments?

The API supports refunds and transaction adjustments. Tax is recalculated based on the adjusted transaction data, and refund activity is reflected accurately in reporting and compliance workflows.

How does the free trial environment work?

The free trial allows teams to explore the Zamp API in a sandbox environment with rate-limited access. The environment is preconfigured for testing, and all trial data is automatically deleted after 30 days.

How is API usage measured?

Usage is based on committed transactions sent to Zamp, not API calls. This aligns pricing with actual business activity rather than request volume.

Which regions are supported?

In addition to U.S. sales tax, Zamp supports Canada, the United Kingdom, the European Union, and other international jurisdictions, depending on use case.