How the Wayfair Decision Impacts Small Businesses: What Changed and What to Do About It

On June 21, 2018, the United States Supreme Court issued its decision in South Dakota v. Wayfair, Inc., overturning the physical presence standard that had governed state sales tax obligations for over 50 years. Under the previous rule, established in the 1992 Quill Corp. v. North Dakota decision, a state could only require a business to collect sales tax if that business had a physical presence — such as an office, warehouse, or employee — in the state.

The Wayfair decision replaced this standard with an economic nexus framework. States can now require remote sellers to collect and remit sales tax based purely on their economic activity in the state, measured by sales revenue, transaction volume, or both. The Court upheld South Dakota's law, which required collection from sellers with more than $100,000 in sales or 200 transactions in the state during the current or prior calendar year.

This ruling fundamentally changed the compliance landscape for every business that sells across state lines, whether through ecommerce, phone orders, wholesale, or services delivered remotely. Before Wayfair, a small online retailer in Oregon selling to customers in 30 states had no obligation to collect sales tax in any of those states unless it had a physical connection there. After Wayfair, that same retailer could have collection obligations in every state where it exceeds the economic nexus threshold.

While the Wayfair decision technically applies to businesses of all sizes, its practical impact falls hardest on small businesses. Large companies like Wayfair, Amazon, and Overstock already had the infrastructure and tax teams to manage multi-state compliance. Small businesses — often run by one or two people — suddenly faced the same obligations without the same resources.

The compliance burden is not just about collecting the right tax rate. Each state has its own registration process, filing frequency, tax rate structure, product taxability rules, and deadlines. A small business selling into 20 states may need to register for 20 separate sales tax permits, file up to 240 returns per year if on monthly filing schedules, track varying rates across thousands of local jurisdictions, and stay current on rule changes in every state.

The cost of compliance software, professional tax assistance, or the time spent managing it all in-house can represent a meaningful percentage of a small business's revenue. According to multiple industry analyses, the average cost of filing a single state sales tax return ranges from $250 to $450 when accounting for time and professional fees. Multiply that across 15 or 20 states and the annual cost can reach $50,000 to $100,000 — a crushing figure for a business generating $500,000 in total revenue.

The Small Business Administration and numerous trade groups raised these concerns before and after the ruling. The Supreme Court itself acknowledged the burden but pointed to South Dakota's law as a model that included protections for small sellers, specifically the $100,000 threshold that was designed to exclude truly small operators.

Every state with a sales tax has adopted some form of economic nexus threshold, but the specifics vary. Understanding where your business crosses these lines is the first step to compliance.

The majority of states use the $100,000 in sales threshold, including Texas, Florida, Illinois, Georgia, Ohio, North Carolina, Michigan, and Pennsylvania, among many others. Some states have set higher bars — California requires $500,000 in sales, while New York and Texas use $500,000 and $500,000 respectively for certain provisions. On the lower end, a few states have set thresholds that can catch even very small sellers.

Many states originally included a 200-transaction threshold as an alternative trigger, meaning you would have nexus if you had either $100,000 in sales or 200 individual transactions in the state. However, the trend since 2022 has been for states to eliminate the transaction count and rely solely on the dollar amount. States that have dropped the transaction test include California, New York, Texas, Colorado, and Georgia. This change was a win for small businesses, because a seller with 201 transactions totaling $15,000 was previously caught in states with the transaction count — an outcome that the Wayfair decision's small seller protections were meant to prevent.

The measurement period also varies. Most states look at the current or prior calendar year, but some use a rolling 12-month period. A handful of states measure on a fiscal year or other basis. Getting the measurement period wrong can mean you miss a filing obligation or register too early.

The question is not whether Wayfair applies to you — it applies to every business selling across state lines. The question is which states you have triggered nexus in and what your obligations are in each one.

Start by pulling your sales data for the past two years, broken down by the state where the customer is located — not where you are located. Destination-based sourcing is the standard in most states, meaning the tax is based on the buyer's address. Group your sales by state and compare the totals to each state's economic nexus threshold.

Pay attention to all your sales channels. Include revenue from your own website, marketplace platforms, wholesale orders, phone and email orders, and any other channel. While marketplace facilitator laws mean you do not need to collect tax on sales that Amazon or eBay facilitated, those sales may still count toward your economic nexus threshold in some states for purposes of determining your obligation on non-marketplace sales.

If you sell services rather than tangible goods, your analysis gets more nuanced. Not all states tax services, and those that do often tax only specific categories. Software as a service, digital goods, consulting, and design work all have different treatment depending on the state. You need to determine both whether you have nexus and whether what you sell is even taxable in each state.

For businesses near the threshold in a given state, it is critical to monitor your sales monthly. Crossing the threshold mid-year triggers an obligation that typically begins within 30 to 60 days, depending on the state. You do not want to discover in April that you crossed the line in January and have been obligated to collect since February.

Once you have identified which states you have nexus in, follow this sequence to get compliant.

Register for a sales tax permit in each state where you have triggered nexus. Never collect sales tax without a valid permit — doing so is illegal in most states and can result in penalties. The registration process varies; some states offer online registration that takes minutes, while others require paper applications that take weeks. Many states participate in the Streamlined Sales Tax Registration System, which allows you to register in multiple states through a single application.

Set up your tax collection systems. If you use an ecommerce platform like Shopify, WooCommerce, or BigCommerce, enable sales tax collection in the settings and verify that the rates and product taxability rules are correct. For more complex situations, integrate a tax calculation engine like Avalara, TaxJar, or Vertex, which can handle rate lookups, product taxability, and exemptions automatically.

Establish a filing calendar. Each state assigns a filing frequency — monthly, quarterly, or annually — typically based on your sales volume in that state. Set calendar reminders well ahead of each deadline. Late filing penalties typically range from 5 to 25 percent of the tax due, and they add up fast across multiple states.

Keep meticulous records. Save all sales data, tax collection records, exemption certificates, and filing confirmations for a minimum of four years — some states have longer statute of limitations periods that extend to seven years.

Small business owners are accustomed to wearing many hats, but multi-state sales tax compliance has become complex enough that professional guidance pays for itself in most cases. If you sell into more than five states, if you sell a mix of products and services with varying taxability, if you use multiple sales channels, or if you have never performed a nexus analysis, working with a specialist is the most cost-effective path forward.

A nexus study from a qualified firm will identify every state where you have current obligations, flag states where you previously had obligations and may have back exposure, and provide a prioritized roadmap for getting registered and filing. Many states offer voluntary disclosure agreements that allow businesses to come into compliance with limited lookback periods and reduced penalties — but these programs must be entered before the state contacts you about an audit.

Nexus Accountant specializes in exactly this type of work: helping small businesses understand their Wayfair-related obligations, register in the right states, set up compliant systems, and stay current as thresholds and rules change. The cost of professional compliance is almost always less than the cost of an audit, back taxes, penalties, and interest.