Unsure where you owe sales or use tax or dealing with legacy compliance pain?
Check Your ExposureA sales tax exposure calculator helps businesses estimate unpaid sales and use tax liability before filing, registering, or responding to an audit. It is designed for businesses that are unsure where tax should have been collected, how much liability may exist, or whether historical exposure needs to be addressed. Sales tax exposure is different from sales tax calculation. Calculation applies tax going forward. Exposure focuses on past activity where tax may not have been collected or remitted correctly.
This page explains what a sales tax exposure calculator does, how the estimates should be interpreted, and when businesses should use one before taking action.
Sales tax exposure refers to unpaid or underpaid sales and use tax from prior periods.
Exposure typically builds when a business:
Exposure often remains hidden until filing, an audit notice, or a review by an accountant or advisor. A full overview is available in the sales tax exposure guide.
A sales tax exposure calculator estimates potential liability by analyzing historical business activity and applying applicable tax rules at a high level.
Most calculators focus on:
The goal is not to produce a filing ready number. The goal is to provide directional clarity so a business understands the scale of potential exposure before deciding next steps.
A sales tax exposure calculator does not replace a detailed compliance review or filing process.
It does not:
This is why exposure analysis should always happen before filing decisions are made. More detail is covered in what to do before filing sales tax.
Businesses commonly use a sales tax exposure calculator when:
Exposure calculators are especially useful for SaaS companies, ecommerce sellers, marketplace sellers, and multi state businesses.
A traditional sales tax calculator focuses on applying the correct rate to a single transaction. A sales tax exposure calculator focuses on historical liability across many transactions and time periods.
Key differences include:
Understanding this distinction helps businesses avoid filing prematurely.
TaxMap’s Sales Tax Exposure Calculator is designed to estimate exposure with clarity rather than overwhelm.
It evaluates:
Results help businesses decide whether exposure exists and which states require further review.
You can access the calculator here: Sales Tax Exposure Calculator
Sales tax exposure varies significantly by state. Rules for sourcing, use tax, marketplace facilitation, and penalties differ.
Businesses often begin exposure analysis by state, especially in large jurisdictions like:
State specific exposure guidance is available in the Texas sales tax exposure overview and California sales tax exposure overview.
Many businesses underestimate use tax exposure. Use tax applies when taxable items are purchased without sales tax and later used in a state.
Exposure calculators should account for:
More detail is available in the use tax explained guide.
After reviewing exposure estimates, businesses typically choose one of three paths:
The right path depends on the size of exposure, risk tolerance, and timing. Next steps are outlined in sales tax exposure next steps.
If your exposure estimate shows potential liability or uncertainty, this is usually a signal to pause before filing and review where tax may actually be owed. You can learn how sales tax exposure is identified to understand what drives risk.
TaxMap is designed for exposure clarity, not forced filing.
TaxMap helps businesses:
This approach allows businesses to stay in control of decisions and timing.
If you are unsure whether your business has unpaid sales or use tax, start by estimating exposure before filing or registering. You can begin by using the sales tax exposure calculator and reviewing your results with context.