A state tax nexus determination is triggered by two things working together: business activity that creates a sufficient connection with a state, and an event that brings that activity to the state's attention or prompts the business to evaluate it. Activities that commonly create nexus include having employees, offices, or property in a state, storing inventory there, sending workers or contractors to perform services, and exceeding a state's sales threshold. Events that commonly prompt a determination include registering for payroll or another tax in the state, data reported by marketplaces, payment platforms, or other agencies, responses to a state nexus questionnaire, an audit, and due diligence for financing or a sale. Because each state and each type of tax has its own rules, the same activity can create nexus for one tax and not another.
This matters because nexus usually builds gradually. A business makes one hire, ships through one new warehouse, or crosses one sales threshold, and the obligation begins without any notice. One thing owners consistently underestimate is that a state often learns about the activity from somewhere other than the business itself.
Nexus Depends on the Type of Tax
States apply different standards to different taxes, so a nexus determination is really several determinations at once.
Sales and Use Tax
Sales tax nexus can arise from physical presence, such as employees, property, or inventory in the state, or from economic nexus, where sales into the state exceed a threshold set by that state. Thresholds, measurement periods, and what sales count toward them vary, and several states have changed their rules recently (see our article on what changed in multi-state tax nexus).
Income and Franchise Tax
Many states assert income or franchise tax nexus based on physical presence, and some use economic or bright-line standards based on sales, property, or payroll in the state. For sellers of tangible goods, federal law limits a state's ability to impose net income tax when in-state activity is limited to soliciting orders, but activities beyond solicitation, including some internet-based activities under certain state interpretations, can remove that protection. Service businesses generally do not have that protection to begin with.
Gross Receipts and Other Business Taxes
Some states impose gross receipts or business activity taxes that may apply at lower thresholds or under different standards than income tax. Businesses expanding into these states can be surprised to find obligations even when they have little profit there.
Payroll-Related Obligations
Employees working in a state generally create withholding, unemployment insurance, and other payroll obligations there, often from the first employee. Those registrations can also signal the business's presence for other tax purposes (see our article on the multi-state trap of hiring remote employees).
Activities That Commonly Create Nexus
The activities that most often lead to nexus include employees working in the state, including remote employees; offices, stores, or other property located there; inventory stored in the state, including in third-party or marketplace fulfillment warehouses; employees or contractors traveling into the state to install, repair, train, consult, or provide other services; delivery using the business's own vehicles; attendance at trade shows or events, depending on the state and the activities involved; and sales into the state that exceed an economic threshold. In practice, this usually shows up as a combination of small activities across several states rather than one obvious expansion.
Events That Prompt a Nexus Determination
Registering for One Tax
Registering for payroll withholding or unemployment insurance in a state, or registering to collect sales tax, can lead the state to ask whether the business also has income, franchise, or other obligations. A new registration may also prompt questions about prior periods.
Third-Party Data
States can draw on information from marketplaces, payment platforms, other state agencies, and information-sharing arrangements to identify businesses with activity in the state. Mismatches between that information and what a business has filed can lead to inquiries.
Nexus Questionnaires
Some states send nexus questionnaires to businesses they believe may have obligations. Questionnaires typically ask about employees, property, inventory, sales, and activities in the state. Answers become part of the record, so responses should be accurate and reviewed carefully before being submitted.
Audits and Related Reviews
An audit of one tax can lead to questions about others, and an audit in one state can surface information relevant to another. Unemployment claims by former workers, insurance audits, and licensing applications can also bring a business's in-state activity to light.
Transactions and Financing
Buyers, investors, and lenders often perform their own nexus review during due diligence. Exposure discovered at that stage can affect price, require escrows or indemnities, or delay closing.
Can a Business Determine Its Own Nexus First?
A question business owners often ask is whether it is better to wait for a state to raise the issue or to evaluate nexus proactively. Generally, a proactive review gives the business more control. It can identify where obligations exist, quantify potential exposure, and choose how to address it. Many states offer voluntary disclosure programs that may limit lookback periods and reduce penalties for businesses that come forward before being contacted. The right approach depends on the states, taxes, and amounts involved, and should be evaluated with a tax advisor (see multi-state tax services).
How to Evaluate Your Nexus Position
A practical nexus review typically maps, for each state, where employees and contractors work, where property and inventory are located, where services are performed, and how much the business sells there by channel. It then compares that activity against each state's rules for each relevant tax. Keeping accurate records of employee work locations, inventory locations, and sales by state, and updating the review annually or whenever the business expands, prevents surprises. Coordinating payroll registrations with tax review is especially important, since hiring in a new state is one of the most common triggers (see HR and workforce compliance).
Where to Start
A state tax nexus determination is triggered by in-state activity that meets a state's standard for a particular tax, combined with an event that brings that activity into view, whether a registration, data match, questionnaire, audit, or transaction. Understanding both sides lets a business evaluate its position on its own timeline rather than a state's. If your business has employees, inventory, services, or significant sales in multiple states, a nexus review is a practical place to start. Secure Accounting can help map your activities, assess your obligations, and plan next steps. When you are ready, start a conversation with our team.