Sales Tax Accuracy Guarantees: What Makes the Zamp Commitment Different

The sales tax landscape has become increasingly complex for businesses. With economic nexus thresholds varying by state and penalties mounting quickly for mistakes, companies need partners they can genuinely trust. That's why Zamp created the Zamp Commitment—a comprehensive accuracy and filing guarantee that goes beyond typical provider promises.

The Zamp Commitment includes both accuracy coverage for API customers and filing protection for managed service clients. If an inaccurate API result triggers a state audit, Zamp covers uncollected sales tax, penalties, and interest, up to the amount you paid over the prior 12 months. For filing customers, Zamp pays any penalties or interest resulting from late submissions due to their error.

We sat down with Matt Grattan, Zamp's Head of Sales and Partnerships, to discuss why the real question isn't whether a provider offers guarantees—it's how they actually step up to the plate to help.

The True Test of Any Guarantee

Sales tax accuracy guarantees often look impressive on paper. Marketing materials feature bold promises and official-looking shields, but the true measure of any guarantee isn't what's promised. It’s what happens when a mistake occurs.

“You can say we have an accuracy guarantee or commitment,” explains Matt Grattan, Head of Partnerships at Zamp. “But the key thing is that it’s important to understand how they would support you if there is an issue. We find that with some companies, the intent is not to actually provide the help if there is an issue to address or take ownership.”

What True Accuracy Coverage Requires

A meaningful accuracy guarantee must address the full spectrum of sales tax complexity. At Zamp, this comprehensive approach starts with how calculations are architected.

• Rooftop-Accurate Calculations. The foundation of any accuracy guarantee is precise rate determination. We maintain all boundaries and rate updates in-house because zip codes aren't always accurate. For example, sales tax boundaries don't always align with zip codes in certain states. This attention to geographic precision extends to supporting all the nuances that impact taxability, from threshold-based exemptions to tax holidays and delivery location rules.
• Taxability Complexity. Beyond rates, certain products and services can face exemptions or partial exemptions based on each state's specific rules. These determinations can depend on cost thresholds, tax holidays, delivery locations, or customer types. The system must handle customer-level exemptions for wholesale, resale, government, and nonprofit transactions while supporting the intricate threshold rules that vary by state.
• Reporting Accuracy. Accurate calculations mean nothing without precise reporting. Each state has unique requirements, formats, and fields. Zamp aligns reports with each state's online filing system to ensure seamless translation from calculation to filing. This attention to detail extends through the entire compliance process, from automated report generation to direct ACH payment processing.

See How Zamp’s Internal Team Maintains Accuracy: How Zamp Ensures Tax Accuracy: What You Need to Know from a Tax Research Expert

When Guarantees Meet Reality

The real differentiator emerges when mistakes happen. During our first year, a situation arose that tested our commitment to accuracy coverage beyond the written terms.

A rapidly growing company needed registration in seven additional states with an effective date of July 1st. The onboarding process went smoothly, with clear communication about the start date for tax collection. However, in the final correspondence, a human error occurred— the customer was told to turn on sales tax collection beginning on August 1st instead of July 1st.

When Zamp's system flagged the discrepancy a week later, $17,000 in uncollected tax liability was found across those seven states.

"We covered the full amount to the penny without hesitation," Grattan recalls. "We met with them, we went through the issue, and we recognized that we had made that one mistake of saying it's August 1st when it was actually July 1st, and we took full ownership of that mistake."

While the guarantee terms might have provided grounds for debate about coverage, the response was immediate and complete. Zamp’s commitment extended beyond legal obligations alone to embody its operational values.

The Partnership Mindset Behind Guarantees

Zamp's accuracy guarantee reflects a broader partnership approach to customer relationships. This mindset encompasses three core elements:

1. Transparency. When issues arise, customers receive complete visibility into what went wrong and how it's being fixed—no finger-pointing or blame deflection—just clear communication about how to get it resolved.
2. Accountability. Mistakes trigger immediate action to fully protect our customers, with coverage that goes beyond typical guarantee limitations.
3. Shared Battle Mentality. Sales tax compliance involves fighting government complexity, outdated systems, and constantly changing regulations. Zamp positions itself alongside customers in this battle, not as a distant vendor selling software.

“We’re on the battlefield together,” Grattan emphasizes. “We’re hand in hand with you. The goal is to get to the point where sales tax is done and it’s done right by Zamp, so you never need to worry about it.”

Building Operational Excellence

The strength of Zamp's accuracy guarantee stems from operational strategies that prioritize precision over shortcuts:

• In-House Content Management. Rather than relying on third-party data sources, Zamp maintains all tax content through in-house research and validation. This control enables faster updates and greater accountability for accuracy.
• Managed Onboarding. Every customer receives hands-on configuration support to ensure proper setup from day one. This "skin in the game" approach eliminates many sources of downstream problems.
• Proactive Monitoring. Systems continuously monitor for discrepancies between registration requirements and collection status, catching potential issues before they become liabilities.

The Culture Behind the Commitment

Zamp's accuracy guarantee is embedded within the organizational culture. We view the guarantee as our operational DNA rather than marketing material.

"It's not just a shield," Grattan explains. "It's how we operate for our customers. It's part of the culture."

This culture is carried out in daily decisions regarding system architecture, customer support, and problem resolution. When accuracy issues arise, the response isn't driven by legal obligations but by a fundamental commitment to customer success.

What This Means for Your Business

For companies evaluating sales tax providers, the lesson is clear: look beyond the marketing materials and guarantee language to understand how providers actually respond when problems occur.

Key questions to ask potential providers include:

• Can you share examples of how you've honored your accuracy guarantee in challenging situations?
• What role do customers play in the accuracy guarantee process?
• How do you handle situations where liability exceeds your stated coverage limits?
• What's your track record for response times when accuracy issues are reported?

The goal isn't to find a provider who never makes mistakes—that's unrealistic in a landscape as complex as sales tax. Instead, the objective is to find a partner whose commitment to accuracy extends beyond contractual obligations to encompass a genuine partnership.

Moving Forward with Confidence

In today's sales tax environment, accuracy guarantees have become table stakes. However, the real value lies in partnering with providers who view these guarantees as the foundation of their customer relationships, rather than mere marketing tools.

Zamp's approach demonstrates that meaningful accuracy coverage requires technical excellence, operational commitment, and cultural alignment around customer success. When these elements combine, accuracy guarantees transform from legal protection into genuine partnership assurance.

For businesses navigating multi-state sales tax compliance, this distinction can mean the difference between costly surprises and confident growth. 

Ready to experience sales tax compliance backed by a guarantee that goes beyond the shield? Contact Zamp to discover how our managed solution combines cutting-edge technology with experts who are genuinely committed to partnership.

About the author

Matt Grattan

Matthew Grattan heads up partnerships and sales for Zamp. He’s worked in the sales tax industry for over 12 years. Matthew currently resides on Bainbridge Island, WA with his wife, 3 kids and dog, Ruthie.