Zamp

Zamp is a sales tax compliance service pairing an API with operational support. It is best suited to finance and accounting teams that want calculations and compliance work under one roof. Its breadth is a strong fit for complex obligations, but less compelling if you only need checkout tax calculations.

Overview

Zamp covers sales tax and Canadian GST, HST, PST, and QST across 13,000 jurisdictions. It combines tax calculations and API access with registration, automated return filing, remittance, and notice handling. Teams can choose done-for-you or done-with-you service, making it possible to delegate more of the work or stay involved in the process.

Calculations use a customer’s building address and geospatial coordinates. Integrations include Adobe Commerce, BigCommerce, NetSuite, Shopify, Stripe, WooCommerce, and Xero. Multi-entity support and a centralized dashboard suit organizations managing obligations across entities; dedicated account management and tax specialists add human support. AICPA SOC 2 compliance is in progress, so teams with a firm certification requirement should account for that status.

Key features

The main strength is the connected compliance workflow. Zamp prepares and submits returns, remits payments directly by ACH, and monitors state portals for notices. It classifies notices, responds, works to resolve issues, and archives them. That can reduce handoffs between calculation software and compliance staff, though teams seeking only a tax calculation API may find this broader service more than they need.

The API sandbox is production-grade but rate-limited, preloaded with remote-seller state registrations, and automatically cleaned up after 30 days. That gives engineering teams a time-bounded way to evaluate integration behavior, not an unrestricted environment for ongoing development. Billing has no per-transaction fees or surprise invoices, which makes transaction volume less likely to create a separate fee line.

Pricing

The Free plan costs nothing and is aimed at teams seeking clarity on tax exposure. It includes a nexus assessment, taxability review, expert consultation, and API sandbox access for 30 days. The free tier is useful for assessment and a short integration evaluation, but it is not a substitute for ongoing filing and remittance.

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 scaling U.S. compliance who want operational coverage alongside calculations. U.S. + Canada also has custom pricing; it adds Canadian GST/HST/PST/QST calculations, registrations, filing and reporting, and cross-border expertise to the U.S. plan. That is the relevant tier for businesses with obligations on both sides of the border.

Assess and diagnose is a custom-priced, one-time option covering nexus assessment, product taxability assessment, historical liability exposure analysis, expert consultation, and an API sandbox. It suits teams that need a defined review rather than recurring managed compliance. The plan details do not give a seat or usage quota for ongoing service.

Platforms

Zamp is available as an API, with integrations for Adobe Commerce, BigCommerce, NetSuite, Shopify, Stripe, WooCommerce, and Xero. Its API orientation suits teams integrating tax into existing systems; it is not presented as a standalone desktop application.

Who it's for

Zamp is strongest for finance and accounting teams that need registration, filing, remittance, and notice management alongside calculation, especially across multiple entities or U.S. and Canadian obligations. The mix of automated workflows and tax-professional support can suit teams that want either delegated or collaborative service. A business needing only a lightweight calculation endpoint, or one requiring completed SOC 2 compliance, should weigh other options.

Pros and cons

• Pros: Calculations, registrations, filing, ACH remittance, and notice handling are combined, reducing the number of separate compliance handoffs.
• Pros: Done-for-you and done-with-you service models accommodate different preferences for delegation.
• Pros: No per-transaction fees or surprise invoices support predictable billing as transaction volume changes.
• Cons: U.S., U.S. + Canada, and assessment pricing is custom, making costs harder to compare upfront.
• Cons: The API sandbox lasts only 30 days and is rate-limited, constraining evaluation and development time.
• Cons: AICPA SOC 2 compliance is in progress, which may not meet teams that require completed certification.

Alternatives

Yonda Tax is worth considering for teams seeking free nexus monitoring and worldwide tax liability calculations, with API and web access. Kintsugi offers a free API plan for global nexus monitoring, exposure and historical liability auditing, and risk assessment.

CCH SureTax offers technology-only, file-and-remit, and fully outsourced options, making it an alternative for teams comparing different levels of filing support. Taxolio is a web-based option with managed compliance shown at $99 a month for two states and additional states at $35 a month, useful for teams comparing a stated per-state price.

ONESOURCE Certificate Manager, Sovos Tax Determination, AccurateTax, and Avalara VAT Registration are other options to compare.

Verdict

Choose Zamp if your team needs tax calculations tied to registration, filing, remittance, and notice handling, with the option to delegate or collaborate. Its integrated service scope is the clearest reason to choose it. Look elsewhere if you need only a narrow calculation API, need a completed SOC 2 certification, or want upfront plan pricing.