April 15 Is Behind You. Sales Tax Exposure Isn't.

Tax season has a way of consuming everything. For CPA and accounting firms, the stretch leading up to April 15 means income tax returns, extensions, client questions, and very little bandwidth for anything else.

…Which is exactly why sales tax compliance tends to fall through the cracks.

Income tax and sales tax run on different calendars, different rules, and different risk profiles. But when the April crunch finally eases, it creates something valuable: an opening. A moment when firms can step back, look at their clients' sales tax footprint, and ask a question that doesn't get asked often enough.

Do we actually know where they have exposure?

Why April Isn't the End

Sales tax obligations don't pause for income tax season. While a client's attention was on filing their federal return, their business kept selling. New states may have crossed economic nexus thresholds. Product lines may have expanded into taxable categories. Remote employees may have quietly created physical nexus in jurisdictions the client didn't know about.

The passage of April 15 doesn't resolve any of that. It just means there's now a window to address it before Q2 closes, before another quarter of liability accumulates, and before state notices arrive.

What a Sales Tax Exposure Review Actually Covers

A meaningful exposure review is a structured look at whether a client's current compliance matches their actual sales footprint. In practice, that means examining several areas:

🔹Nexus status
Where is the client selling, and have they registered in every state where they've crossed economic thresholds? Economic nexus rules vary by state, and the thresholds themselves shift. A client who was under the limit in January may have crossed it in March.

🔹 Registration gaps
A client may know they have nexus somewhere but have never completed registration. That gap is itself a liability, because the clock on back taxes starts at the point of nexus, not the point of registration.

🔹 Product taxability
Not everything is taxable everywhere, and the rules change. Digital products, software subscriptions, food, and professional services all carry varying taxability rules across states. Firms serving SaaS or ecommerce clients should pay particular attention here, as these categories see the most regulatory movement.

🔹 Filing accuracy
Even clients who are registered and filing may be doing so incorrectly: wrong rates, wrong jurisdictions, exemptions applied without current documentation. These errors are correctable, but only once they're visible.

🔹 Exemption certificate status
B2B clients with exempt customers need current certificates on file. An expired or missing certificate means collected tax that should have been remitted, or liability that should have been documented.

The Cost of Finding Out Later

Sales tax exposure compounds. The earlier an exposure gap is identified, the more options exist for addressing it cleanly.

Many states offer Voluntary Disclosure Agreements (VDAs) that can limit the lookback period and reduce or eliminate penalties for firms that proactively come forward. Those programs are generally more accessible before a state initiates contact than after.

A post-April review won't surface every issue immediately. But it creates a current-state baseline that makes surprises less likely and remediation more manageable.

How Automation Changes the Review Process

The traditional approach to exposure analysis involves pulling transaction data by state, cross-referencing nexus thresholds, checking registration status, and manually reviewing product categories. For firms managing a large client book, that process is time-intensive enough that it tends to happen reactively, after a state notice, rather than proactively.

Automation changes the equation. Platforms like Kintsugi can run exposure analyses quickly across all jurisdictions, monitor nexus thresholds in real time, and flag registration gaps or filing inconsistencies without requiring staff to manually track each state's rules. The result is that a review that might take days of manual work can surface actionable findings in a fraction of the time, and firms can run them more often.

For firms that want to offer sales tax advisory as a recurring service, this kind of automation is what makes consistent, scalable delivery possible. Staff spends less time on work that can be automated, and more time on the advisory conversations clients actually need.

What to Do Now

April's filing deadline has passed. That's not a reason to wait until next April to look at sales tax exposure. For many clients, the window between now and mid-year is the right time to run the check, while there's still room to address what's found without urgency driving the decisions.

A structured exposure review now can catch registration gaps before they grow, identify filing errors while correction is still straightforward, and position firms as the advisor who caught the problem rather than the one who learned about it from a state notice.

Kintsugi's partner platform gives firms a practical way to run these reviews and manage ongoing compliance across their client base. Learn more about how Kintsugi supports CPA and accounting firms: become a partner.