Overview

Zamp handles sales tax and Canadian GST, HST, PST, and QST across 13,000 jurisdictions. Alongside API access and tax calculations, it offers done-for-you or done-with-you sales tax handling. That choice matters: teams can delegate more of the compliance workload or remain involved, rather than stitching separate tools and service providers together.

Calculations draw on a customer’s building address and geospatial coordinates, a useful basis for businesses where rooftop-level accuracy matters. Integrations include Adobe Commerce, BigCommerce, NetSuite, Shopify, Stripe, WooCommerce, and Xero. More than 1,200 finance and accounting teams have saved thousands of hours with Zamp.

Key features

Zamp’s operational scope extends well beyond tax calculation. It prepares and submits returns, files automatically, and remits tax directly by ACH. It also monitors state portals, classifies notices, responds to them, resolves issues, and archives the correspondence. Putting those jobs under one service can reduce internal follow-up, particularly for teams with obligations across multiple entities.

Multi-entity support, a centralized dashboard, and dedicated account management address the needs of finance teams overseeing more than one business. Support from tax professionals, former auditors, and senior tax specialists adds expertise for compliance questions. AICPA SOC 2 compliance is in progress, so organizations that require completed SOC 2 compliance should not treat that status as equivalent to certification.

The production-grade API sandbox gives prospective users a way to assess nexus and taxability, consult an expert, and exercise API access before moving to a paid service. It is rate-limited, preloaded with remote-seller state registrations, and lasts 30 days before its data is cleaned up automatically. That makes it suitable for a bounded evaluation, not an ongoing free production workflow.

Pricing

Zamp uses paid pricing for its compliance services, with a free tier and a 30-day trial. Billing is predictable, with no per-transaction fees or surprise invoices—a meaningful advantage for teams wary of usage-based tax bills. The plans do not state seat quotas, and the paid U.S. coverage prices are custom pricing.

Free — 0.00 USD per free: Includes nexus assessment, taxability review, expert consultation, and a 30-day API sandbox. It suits teams seeking clarity on tax exposure or evaluating the API; rate limits and automatic cleanup constrain its use.
Assess and diagnose — custom pricing: A one-time package covering nexus assessment, product taxability, historical liability exposure, expert consultation, and an API sandbox. It fits teams that need a focused review rather than ongoing compliance operations.
U.S. — custom pricing: Adds rooftop-accurate calculations, nexus monitoring and registration, automated filing and remittance, notice management, and dedicated U.S. tax expertise. It is the more relevant option for scaling teams with U.S. filing obligations that want managed support.
U.S. + Canada — custom pricing: Includes U.S. plan features plus Canadian GST/HST/PST/QST calculations, registration, filing and reporting, and cross-border tax expertise. It fits businesses with obligations on both sides of the border; teams operating only in the U.S. would not need the added Canadian coverage.

The free tier is an assessment and sandbox offer, not a substitute for registration, filing, or remittance services. Published pricing also does not provide a basis to compare the cost of the U.S. plans against a narrower API-only option.

Platforms

Zamp is available through an API, with integrations for Adobe Commerce, BigCommerce, NetSuite, Shopify, Stripe, WooCommerce, and Xero. It is a fit for teams building tax into connected commerce and finance workflows; a standalone web interface is not among its stated platforms.

Who it's for

Zamp is strongest for finance and accounting teams that need accurate calculations alongside registrations, returns, remittance, and notice handling. Multi-entity support and specialist account support make it relevant to more complex operations, while the done-for-you and done-with-you models accommodate different levels of internal involvement. It is less suited to businesses seeking only a lightweight checkout calculation API or those unable to consider custom-priced compliance services.

Pros and cons

Pro: Calculation, registration, automated filing, ACH remittance, and notice management sit within one service, reducing the number of compliance handoffs.
Pro: Rooftop-accurate calculations and coverage across 13,000 jurisdictions support businesses with detailed location-based tax needs.
Pro: The free tier combines nexus and taxability review with expert consultation and a production-grade sandbox, giving teams a practical way to evaluate exposure and API behavior.
Con: The sandbox is rate-limited and expires after 30 days with automatic cleanup, so it cannot serve as a continuing free environment.
Con: U.S. and U.S. + Canada pricing is custom, making budget comparisons harder before a sales conversation.
Con: AICPA SOC 2 compliance is in progress, which may not satisfy organizations that require completed compliance.

Alternatives

Consider Yonda Tax if a free nexus-monitoring plan and web access alongside its API better match your needs; its U.S. sales tax plan also has no stated price.

Kintsugi is another freemium API option, with a free plan that does not require a credit card and includes global nexus monitoring and exposure auditing.

CCH SureTax offers a choice between technology-only returns, filing and remittance, or fully outsourced service, making it worth considering when those service tiers are the deciding factor.

For a web-based managed service with a published two-state price of 99.00 USD per month, consider Taxolio; its additional-state plan is 35.00 USD per month.

Sovos Tax Determination is another paid API and web option for teams prepared to contact the provider for pricing.

AccurateTax is a paid API and web alternative with a free trial and options for basic calculations or fully managed service.

Numeral offers a free monitoring plan with nexus alerts and liability audits, making it an option for teams prioritizing exposure monitoring.

Avalara VAT Registration is another paid API and web option.

Browse Sales Tax Software, Tax Engine Software, and Tax Compliance Software for more options by category.

Verdict

Choose Zamp if your team wants tax calculations and API access tied to managed U.S. or cross-border compliance, especially when notice response and direct remittance would otherwise consume staff time. Its operational breadth and specialist support are the main reasons to choose it. Look elsewhere if you need only a simple calculation API, or if custom pricing and in-progress SOC 2 compliance do not fit your budget or requirements.

	VATCalc Calculator	Zamp
Free plan	No	Yes
Free trial	Yes	No
Paid from	—	Free
Open source	No	No
Platforms	api, Web	api
Real-time calculation	Yes	—
Tax types	multiple	—
API access	Yes	Yes
Commerce connectors	Yes	—
Free plan	—	No

VATCalc Calculator vs Zamp

VATCalc Calculator

Zamp