Small Business Sales Tax Nexus Threshold State Compliance Guide — Thresholds By

The $100K Question: When Your Revenue Crosses a State Line

Sales tax nexus thresholds by state are the revenue or transaction levels that determine when an out-of-state business must collect and remit sales tax in a given state. The 2018 South Dakota v. Wayfair decision fundamentally changed the landscape for small businesses, allowing states to require remote sellers to collect sales tax based on economic activity rather than physical presence alone.¹

For a growing company, tax obligations can expand faster than the customer list. A SaaS company based in Austin with customers in 12 states might not think about sales tax until an audit notice arrives. The trigger is deceptively simple: once your sales into a state exceed that state's economic nexus threshold, you are legally required to register, collect, and remit sales tax there.

Forty-five states plus Washington, D.C. now impose economic nexus thresholds.² Most set the bar at $100,000 in annual sales or 200 separate transactions, but the exact numbers vary. For example, a business selling $95,000 worth of software subscriptions into California faces no obligation. Add one more contract worth roughly $6,000, and the compliance burden activates immediately.

The risk is cumulative. A founder might assume that $50,000 in sales spread across five states keeps them under every radar. But suppose a business hits $110,000 in a single state where the threshold is $100,000 — that state expects registration and back-tax collection from the first dollar.

What a Sales Tax Nexus Threshold Actually Means for Your Business

Economic nexus means an out-of-state seller must collect and remit sales tax even without a physical presence if sales exceed the state's threshold.³ This is not a suggestion. States have audit teams that cross-reference business license databases, trade show registrations, and even shipping data to identify unregistered sellers.

Consider a hypothetical software company based in Denver with $2 million in annual recurring revenue. Their customer base is concentrated in Colorado, California, Texas, and New York. If California sales hit the state's economic nexus threshold of $500,000, the company must register with the California Department of Tax and Fee Administration, collect the applicable rate (which varies by county and city), and file returns monthly or quarterly.

The penalty for missing this? Back taxes, interest, and potential penalties that can reach, for example, 25% of the tax due. A $15,000 uncollected tax bill can balloon to $22,000 within 18 months.

How Economic Nexus Laws Vary by State and Category

Not all states use the same formula. The variation creates complexity that catches founders off guard.

Alaska removed its 200-transaction threshold effective January 1, 2025, moving to a pure $100,000 sales threshold.² Indiana did the same effective January 1, 2024.² These changes matter because a business with many small transactions — say a retailer selling $40 widgets — could trigger nexus in a transaction-count state long before hitting the dollar threshold.

Vermont's economic nexus threshold is $100,000 in sales or 200 transactions.⁴ A business selling $95,000 worth of Vermont maple syrup equipment would not trigger nexus. Add five more orders totaling, for example, $6,000, and the obligation activates.

The $100,000 Threshold States You Need to Track Today

The majority of states with economic nexus laws use $100,000 in sales as the primary trigger. The table below covers all states using this threshold:

A business selling, for example, $95,000 into Pennsylvania faces no obligation. A single $6,000 contract pushes them over, and registration is required within 30 days of crossing the threshold.

Marketplace Facilitator Rules That Change Your Liability

Marketplace facilitator laws in most states hold platforms like Amazon, Etsy, and eBay responsible for collecting and remitting sales tax on behalf of third-party sellers.⁵ This changes the nexus calculation significantly.

If a business sells through Amazon into California and through its own website into California, the marketplace sales do not count toward the business's own nexus threshold. Amazon collects and remits tax on those sales. Only the direct sales count toward the California threshold.⁶

The trap: many founders assume marketplace sales are invisible. They are not. States can still audit the business for its direct sales, and marketplace facilitator laws do not eliminate the business's obligation to track its own thresholds.

A hypothetical business selling $450,000 through Amazon into California and $60,000 through its own website would not trigger California nexus. But if that same business adds a direct sales channel and hits $510,000 in direct sales, registration is required.

Multi-State Inventory and Remote Worker Nexus Risks

Physical presence nexus still exists. Storing inventory in a third-party warehouse in another state creates nexus. Having a remote employee working from another state creates nexus. Attending a trade show and taking orders can create nexus.

A business with a fulfillment center in Nevada and customers in California has physical nexus in Nevada and economic nexus in California. Both states require registration.

Remote workers are a growing risk. A company with 15 employees, one of whom works remotely from Arizona, has physical nexus in Arizona. The state expects sales tax collection on all sales to Arizona customers, regardless of whether the economic threshold is met.

A business with $1.5 million in revenue, a warehouse in Texas, and a remote employee in Colorado must register in both states. The Colorado employee alone creates nexus, even if Colorado sales are only $20,000.

How to Monitor Thresholds Without a Dedicated Tax Team

Most SMBs cannot afford a full-time tax compliance team. The solution is systematic tracking using available tools.

A spreadsheet tracking sales by state, updated monthly, catches threshold crossings before they become problems. The key fields: state, YTD sales, transaction count, threshold type, and registration status.

Sales tax automation software connects to the business's sales platform and calculates nexus exposure in real time. For a business with $2 million in revenue across 10 states, the cost is typically under $200 per month. CurrentCFO offers threshold monitoring as part of its fractional CFO services.

What Happens When You Cross a State's Nexus Threshold

Crossing a threshold triggers a legal obligation to register, collect, and remit sales tax. The timeline varies by state, but most require registration within 30 to 60 days of crossing the threshold.

The registration process involves:

1. Applying for a sales tax permit in the state
2. Determining the correct tax rate (state + local)
3. Setting up tax collection in the sales platform
4. Filing returns on the state's schedule (monthly, quarterly, or annually)
5. Remitting collected tax by the filing deadline

Failure to register results in back-tax assessments. States use data from business license databases, trade show registrations, and shipping records to identify unregistered sellers. A business that crossed a threshold 18 months ago and never registered faces back taxes, interest, and penalties.

A hypothetical business that crossed California's $500,000 threshold 24 months ago and never registered would owe approximately $45,000 in uncollected tax, plus interest at 5% per year, plus a 10% late registration penalty. Total liability: approximately $55,000.¹

Your Next Step

Run a sales-by-state report for the last 12 months. Compare each state's total to its economic nexus threshold. If any state exceeds the threshold and you are not registered, contact a sales tax professional or use a voluntary disclosure program to come into compliance before the state contacts you. For a free threshold review, email [email protected].