Overview

Zamp covers sales tax and Canadian GST, HST, PST, and QST, with 13,000 jurisdictions covered. It pairs tax calculations and API access with operational services, including registrations, automated return filing, ACH remittance, and notice resolution. Teams can choose a done-for-you or done-with-you service model, a useful distinction for companies that want either more delegated compliance or more involvement.

Calculations use a customer’s building address and geospatial coordinates for precise tax treatment. Integrations include Adobe Commerce, BigCommerce, NetSuite, Shopify, Stripe, WooCommerce, and Xero. More than 1,200 finance and accounting teams have used Zamp.

Key features

The service goes beyond calculation: Zamp prepares and submits returns, remits payments by ACH, and monitors state portals for notices. It classifies, responds to, resolves, and archives those notices. That operational coverage can reduce the handoffs between tax software and internal staff, but teams should weigh the managed-service model against a narrower calculation API if they only need tax at checkout.

Multi-entity support, a centralized dashboard, and dedicated account management address administrative needs across organizations. Support includes tax professionals, former auditors, and senior tax specialists. AICPA SOC 2 compliance is in progress, so teams with certification requirements should factor that status into procurement.

Pricing

Zamp’s pricing model is paid, with pricing on request and a 30-day trial. The Free plan is 0.00 USD per free and includes a 30-day sandbox; its free tier also includes nexus assessment, taxability review, expert consultation, and API sandbox access. The sandbox is described as production-grade, preloaded with remote-seller state registrations, rate-limited, and automatically cleaned up. That makes it useful for evaluation, but its time and rate limits constrain sustained integration work.

The U.S. plan has custom pricing and includes rooftop-accurate calculations, nexus monitoring and registration, automated filing and remittance, notice management, and dedicated U.S. tax expertise. It fits teams seeking end-to-end U.S. compliance rather than calculations alone.

U.S. + Canada also has custom pricing. It adds Canadian GST, HST, PST, and QST calculations, registrations, filing and reporting, and cross-border tax expertise to the U.S. plan. This is the relevant tier for teams managing both markets, though the custom price makes a direct budget comparison harder.

Assess and diagnose has custom pricing and is a one-time engagement covering nexus and product taxability assessments, historical liability exposure analysis, expert consultation, and an API sandbox. It is a focused starting point for teams that want an exposure review before committing to ongoing compliance services.

Zamp says billing has no per-transaction fees or surprise invoices, a useful contrast for teams sensitive to transaction-based cost growth.

Platforms

Zamp is available via API and integrates with Adobe Commerce, BigCommerce, NetSuite, Shopify, Stripe, WooCommerce, and Xero. Its platform fit is strongest for teams building tax into an existing commerce or finance stack; it is not presented as a broad desktop or mobile app offering.

Who it's for

Zamp is best suited to finance and accounting teams that need tax calculation connected to registration, filing, remittance, and notice management, especially when operating across U.S. and Canadian tax regimes. Engineering teams can evaluate the API through the sandbox. Teams seeking only a lightweight calculation API, a published plan price, or a completed SOC 2 status may have reason to look elsewhere.

Pros and cons

Pros

Compliance operations beyond calculation: Managed registrations, automated filing, ACH remittance, and notice resolution can reduce internal coordination work.
North American coverage: The U.S. + Canada plan extends the U.S. service with Canadian tax calculations, registrations, filing, and expertise.
Predictable billing approach: No per-transaction fees or surprise invoices helps avoid transaction-driven billing uncertainty.
Stack connections: Integrations span commerce, finance, and payment tools including Shopify, NetSuite, Stripe, and Xero.

Cons

Custom pricing for core plans: U.S. and U.S. + Canada costs are not published, complicating budget comparisons.
Constrained API evaluation: The 30-day sandbox is rate-limited and automatically cleaned up, so it is not a durable test environment.
SOC 2 compliance is in progress: Organizations requiring completed certification should account for that status in their vendor review.

Alternatives

For a broader shortlist, see Tax Compliance Software, Sales Tax Software, and Tax Engine Software.

LOVAT is a freemium, multi-platform alternative with a free plan and free trial; consider it when those access options and Android, iOS, or web platforms matter.

Avalara AvaTax offers a Core Compliance plan at 79.00 USD per month for annual revenue below $50M and 12,000+ U.S. jurisdictions; choose it when that published monthly plan and U.S. coverage fit the requirement.

Numeral offers a free nexus study, threshold alerts, monitoring, and exposure audits in its Monitoring plan; it is a fit when nexus visibility is the main need.

Kintsugi has a free plan for global physical and economic nexus monitoring, exposure auditing, and risk assessment; consider it for a free starting point focused on those tasks.

Stripe Tax offers no-code and API integration plans for tax calculations and collections; choose it when those integrations are the priority.

Sovos Tax Determination is a paid API and web option with pricing handled through a call.

ONESOURCE Indirect Compliance is a paid API option.

TaxBandits offers a 19.00 USD per month Basic plan and a free plan; consider it when its broader Android, iOS, web, and extension platform support is relevant.

Verdict

Choose Zamp if your team wants tax calculations and API access backed by managed registration, filing, remittance, and notice handling, particularly across U.S. and Canadian tax. Its main advantage is the scope of operational coverage; its main drawback is custom pricing for the plans most teams are likely to need. Teams requiring a completed SOC 2 status, sustained sandbox access, or a clearly priced core plan should compare alternatives.

	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