If you’re selling online and shipping to different states, there’s a good chance you have a sales tax obligation you don’t even know about.
Sales tax used to be pretty straightforward for small businesses. You had a shop, you knew what state you were in, and you collected sales tax from your local customers. Easy.
Then e-commerce happened. And then, in 2018, a Supreme Court decision called South Dakota v. Wayfair changed everything. If you’re selling products online and shipping across state lines, your sales tax obligations are almost certainly more complex than you realize.
What the Wayfair Decision Changed
Before 2018, states could only require businesses to collect sales tax if they had a physical presence there — an office, a warehouse, an employee. Wayfair changed that by establishing the concept of ‘economic nexus.’ Now, you can trigger a sales tax obligation in a state simply by making enough sales there — even if you’ve never set foot in the state.
Every state that has a sales tax has now adopted economic nexus rules. The most common threshold is $100,000 in sales or 200 transactions in a state per year. Cross that threshold and you’re required to register, collect, and remit sales tax in that state.
 If you’re selling on Amazon, Etsy, Shopify, or any other platform and shipping nationwide, you need to know where you’ve crossed economic nexus thresholds.
Marketplace Facilitator Laws — Some Good News
There is one thing that has gotten easier for many online sellers. Most states now have marketplace facilitator laws, which require platforms like Amazon, eBay, and Etsy to collect and remit sales tax on behalf of third-party sellers. If you’re selling exclusively through these marketplaces in a given state, you may not have an additional obligation.
But this only applies to sales through those facilitated platforms. If you have your own website or sell through other channels, you’re still responsible for collecting and remitting on those sales.
The Risks of Non-Compliance
States have gotten increasingly aggressive about pursuing out-of-state sellers for uncollected sales tax. They have access to information from platforms, payment processors, and even customs data. Penalties and interest on uncollected sales tax can add up fast — especially if you’ve been selling for years and this is the first time you’re looking at it.
The good news is that many states have voluntary disclosure programs that allow businesses to come into compliance with reduced penalties. But you have to know to ask for them.
What to Do If You’re Not Sure Where You Stand
The first step is figuring out where you actually have nexus. That means pulling your sales data by state and comparing it against each state’s thresholds. It’s tedious but important. If you’ve been selling for a while and haven’t been tracking this, there may be some back-filing to do.
We work with e-commerce businesses to get their sales tax compliance in order — from nexus analysis to registration to ongoing filing. It’s one of those areas where getting professional help upfront is almost always less expensive than cleaning up the mess later.
Ready to Get This Off Your Plate?
At Basc Expertise, we handle sales tax compliance, e-commerce accounting, and state registrations so you can focus on running your business. Reach out to us at www.bascexpertise.com — we’d love to chat.