Unsure where you owe sales or use tax or dealing with legacy compliance pain?
Check Your ExposureA sales tax nexus calculator helps businesses determine where they have an obligation to register, collect, and remit sales or use tax. Nexus is the legal connection between a business and a state that creates tax responsibility. Sales tax nexus rules have expanded significantly since economic nexus laws were introduced. Many businesses now have nexus in states where they have no physical presence.
This page explains what a sales tax nexus calculator does, how nexus is created, and when businesses should use a calculator before registering or filing.
Sales tax nexus is the threshold that determines whether a business is required to collect and remit sales or use tax in a state.
Nexus can be created through:
Once nexus is established, a business may be required to register and collect tax. A broader explanation is available in the sales tax nexus overview.
Economic nexus laws require businesses to collect sales tax based on economic activity alone, even without physical presence.
Common economic nexus triggers include:
Many businesses unknowingly cross these thresholds and continue selling without registering. State specific economic nexus rules are summarized in the economic nexus by state guide.
A sales tax nexus calculator evaluates whether a business has established nexus based on available activity data.
Most calculators analyze:
The goal is to identify where registration and collection obligations may exist before a business takes action.
A sales tax nexus calculator does not replace a legal determination or compliance review.
It does not:
This is why nexus analysis should happen before filing or collecting tax. More context is covered in what to do before filing sales tax.
Businesses commonly use a sales tax nexus calculator when:
Nexus calculators are especially useful for ecommerce sellers, SaaS companies, marketplace sellers, and multi state businesses.
Nexus determines whether tax should have been collected. Exposure determines how much liability may exist.
A business may:
This is why nexus analysis should be paired with exposure analysis. More detail is available in the sales tax exposure overview.
TaxMap’s Sales Tax Nexus Calculator is designed to identify nexus with clarity and context.
It evaluates:
Results help businesses understand where nexus likely exists and where deeper review is required.
You can access the calculator here: Sales Tax Nexus Map
Sales tax nexus rules vary significantly by state.
Some states:
Businesses often begin nexus analysis in large states such as Texas, California, New York, and Florida. State level nexus guidance is available in the Texas sales tax nexus overview and California sales tax nexus overview.
Businesses frequently make the following mistakes when evaluating nexus:
These mistakes often lead to unnecessary penalties or cleanup work.
After identifying potential nexus, businesses typically choose one of three paths:
The right path depends on timing, exposure size, and audit risk. Next steps are outlined in sales tax exposure next steps.
If your nexus results indicate registration requirements or uncertainty, this is often a signal to pause before filing and review potential exposure. You can learn how sales tax exposure is identified to understand the risks of late registration.
TaxMap is designed to help businesses understand obligations before acting.
TaxMap helps businesses:
This approach reduces risk and prevents unnecessary compliance errors.
If you are unsure where your business must register and collect sales tax, start by identifying nexus before filing or collecting. You can begin by using the sales tax nexus calculator and reviewing the results in context.