Economic Nexus: When Online Sellers Must Collect Sales Tax
Learn how economic nexus sales tax rules work, how to track state thresholds, and what marketplace facilitator laws mean for your online store.
Photo: Pixabay
On this page 7 sections
- Physical Nexus vs. Economic Nexus: What Changed for Remote Sellers
- How Economic Nexus Sales Tax Thresholds Work
- Marketplace Facilitator Laws: When Amazon or Etsy Collects for You
- Tracking Sales Tax Nexus by State
- Registering, Collecting, and Filing Once You Cross a Threshold
- Fixing Past Exposure With Voluntary Disclosure Agreements
- Next Steps for Online Sellers
Key takeaways
- Economic nexus can require you to collect sales tax in a state where you have no physical presence once your sales there cross that state's threshold.
- Each state sets its own dollar and transaction thresholds, measurement period, and rules for which sales count, so track sales by ship-to state.
- Marketplace facilitator laws usually shift collection on marketplace sales to the platform, but your own Shopify or WooCommerce storefront remains your responsibility.
- If you crossed thresholds in the past without collecting, a voluntary disclosure agreement may limit penalties and lookback. Talk to a tax professional first.
If you sell online and ship to customers across the country, economic nexus sales tax rules can require you to collect and remit sales tax in states where you have no office, warehouse, or employees. Whether you owe depends on how much you sell into each state, not where you are located. This guide explains how economic nexus differs from physical nexus, how state thresholds work, and how marketplace facilitator laws change your obligations. It also shows how to track sales by state, what to do once you cross a threshold, and how to clean up past exposure.
This article is general information, not tax or legal advice. Sales tax rules change often and vary by state. Confirm your obligations with a qualified CPA or tax attorney.
Physical Nexus vs. Economic Nexus: What Changed for Remote Sellers
"Nexus" is the connection between your business and a state that gives the state the right to require you to collect its sales tax.
For decades, that connection generally had to be physical. Physical nexus can come from things like:
- An office, store, or warehouse in the state
- Employees or, in some cases, remote workers living there
- Inventory stored in the state, including inventory held in a third-party fulfillment center
- Regular in-person activity, such as sales reps or, in some states, trade show attendance
That changed after a U.S. Supreme Court decision opened the door for states to base sales tax collection duties on a remote seller's sales activity, not only on physical presence. Afterward, states with a sales tax adopted economic nexus laws that set a level of sales into the state. Once a seller crosses that level, collection is required.
Two points matter for online stores:
- Physical nexus still exists. Economic nexus was added on top of it. If you use a fulfillment network that stores your goods in several states, you may have physical nexus in those states regardless of sales volume.
- Your home state counts too. Most sellers already have nexus where they are based, whatever they sell elsewhere.
How Economic Nexus Sales Tax Thresholds Work
So, do I need to collect sales tax in other states? The answer comes down to each state's threshold, and states do not share one standard. When you look up a state's rule, check these elements:
| Element | What to Check |
|---|---|
| Dollar threshold | The amount of sales into the state that triggers nexus |
| Transaction count | Whether a number of separate sales also triggers nexus, and whether the test is "or" or "and" |
| Measurement period | Previous calendar year, current year, trailing 12 months, or another window |
| Which sales count | Gross sales, retail sales only, or taxable sales only, and whether marketplace sales are included |
| Effective date | When you must register after crossing, which may be immediately, the next month, or the next year |
Many states use a dollar threshold. Some also use a transaction count, and some have changed or dropped their transaction tests over time. Always check the current rule on the state's department of revenue website.
Why Transaction Counts Catch Small Sellers
Transaction-count tests can trigger nexus for stores with low average order values. A shop selling inexpensive accessories, prints, or consumables can rack up many small orders in a state while staying well below the dollar threshold. If a state uses an "or" test, the transaction count alone can create nexus.
An Illustrative Example
The figures below are hypothetical and do not reflect any real state's rules.
| Hypothetical State | Threshold Rule (Illustrative) | Your Sales There (Illustrative) | Nexus? |
|---|---|---|---|
| State A | $X in sales or Y transactions | Under $X, but more than Y orders | Yes, by transaction count |
| State B | $X in sales only | Under $X, many orders | No |
| State C | $X in taxable sales | Over $X gross, but mostly exempt goods | Possibly not, so confirm the definition |
The lesson is that the same sales pattern can create nexus in one state and not another.
Marketplace Facilitator Laws: When Amazon or Etsy Collects for You
Marketplace facilitator laws require large online marketplaces to collect and remit sales tax on sales made through their platforms. States with a sales tax have broadly adopted these laws. If you sell on Amazon, Etsy, eBay, or Walmart Marketplace, the platform generally handles collection on those orders in states where these laws apply.
What these laws do not cover is just as important:
| Sales Channel | Who Typically Collects | Notes |
|---|---|---|
| Marketplace orders (Amazon, Etsy, etc.) | The marketplace | Confirm in your seller reports |
| Your own Shopify store | You | Shopify tools can calculate tax, but you remain the seller |
| Your own WooCommerce site | You | Tax plugins calculate, and you register and file |
| Wholesale or B2B orders | You | Collect exemption or resale certificates |
| Social commerce and payment links | Depends on the platform | Check whether it acts as a facilitator |
How Marketplace Sales Affect Your Thresholds
States differ on whether marketplace sales count toward your economic nexus threshold. In some states they count even though the marketplace collected the tax. In others they are excluded. A seller with strong Amazon volume and a small Shopify store could cross a threshold on combined sales and need to register for the Shopify orders alone.
Some states may also expect marketplace sellers to register or file returns even when the marketplace collects everything. Check each state where you have significant marketplace volume.
Dropshipping Wrinkles
Dropshippers face two extra questions:
- Your sales to customers. You are usually the retailer, so economic nexus applies to your storefront sales like any other seller.
- Your supplier's sales to you. Suppliers may ask for a resale certificate. Without one that the ship-to state accepts, some suppliers may charge you sales tax on the wholesale purchase. Rules on which certificates states accept vary, so ask your tax advisor.
Tracking Sales Tax Nexus by State
You cannot manage sales tax nexus by state without clean data. Sales tax obligations for shipped orders are commonly tied to where the order is delivered, so organize your records by ship-to state, not by billing address or customer location.
Build a Monthly Nexus Tracker
A simple spreadsheet works for many small stores. For each state, record:
- Gross sales shipped to that state
- Number of transactions
- Sales through marketplaces (tracked separately)
- Sales through your own storefront
- Exempt or wholesale sales
- The state's threshold and measurement period
- Percentage of threshold reached
Set an alert level, such as when you reach a set share of a state's threshold, so you have time to prepare before you cross it. A holiday rush or a viral product can push you over in a single month.
Where to Pull the Data
- Store platform reports. Shopify and WooCommerce can export orders by shipping address.
- Marketplace tax reports. Amazon and Etsy provide reports showing tax collected by state.
- Payment processor and gateway reports. These help you confirm that order totals match what was settled. A monthly credit card reconciliation process catches refunds and chargebacks that can change your net sales by state.
- Accounting software. Syncing sales data through a QuickBooks integration helps keep tax collected separate from revenue.
If you are still setting up your checkout and reporting, our guide to ecommerce payment processing setup covers how gateways, processors, and store platforms fit together. MannyPay offers online payment processing for ecommerce stores with gateway options that connect to Shopify and WooCommerce. If your store uses Shopify Payments, see our guide on what to do if your Shopify Payments account is suspended. If you're weighing which payment options to offer, see the tradeoffs of adding PayPal to checkout.
Registering, Collecting, and Filing Once You Cross a Threshold
Once you cross a state's threshold, follow this sequence.
1. Register Before You Collect
Apply for a sales tax permit with the state's department of revenue. Some states do not allow you to collect sales tax without a permit, so register first rather than charging tax and registering later.
2. Set up Tax Calculation Correctly
- Sourcing. Many states tax remote sales based on the destination, meaning the customer's ship-to address, including local rates. Local rules can be detailed. Our article on Seattle's destination-based sales tax rules for online orders shows how this works in one city.
- Product taxability. Clothing, food, supplements, and digital goods are treated differently from state to state. Map your products to the right tax categories.
- Shipping charges. Some states tax shipping and others do not, depending on how it is billed.
- Exemptions. Collect and store exemption certificates for wholesale and other exempt buyers.
3. File on Schedule, Even With Zero Sales
States assign a filing frequency, often based on your volume. Missing a return can trigger penalties even if you owed nothing. File zero returns when required.
4. Treat Collected Tax as Someone Else's Money
Sales tax you collect belongs to the state. Set it aside in a separate account or account for it in your cash planning. A 13-week cash flow forecast built from your sales data helps you see when large tax payments come due. Also remember that card processing fees are generally charged on the full transaction amount, including the tax portion, so factor that into your margins.
Fixing Past Exposure With Voluntary Disclosure Agreements
Many sellers discover they crossed thresholds months or years ago without collecting. The uncollected tax usually becomes your liability, because you generally cannot go back and bill customers for it.
A voluntary disclosure agreement (VDA) is a program many states offer so businesses can come forward on their own. Terms vary by state, but VDAs commonly offer:
- A limited lookback period instead of the full period of noncompliance
- Waiver or reduction of penalties
- In some states, reduced interest
How the Process Generally Works
- Quantify exposure. Use your nexus tracker to estimate when you crossed each threshold and what tax would have been due.
- Prioritize. Focus on the states with the largest exposure first.
- Approach the state, often anonymously. A tax professional can often contact the state for you before your business name is disclosed.
- Register and file. Once the agreement is signed, pay the agreed amount and begin filing going forward.
Eligibility often depends on the state not having contacted you first. If you receive a nexus questionnaire or audit notice, VDA options may narrow, so act early. Work with a CPA or sales tax specialist on any disclosure.
Next Steps for Online Sellers
- Export the last 12 to 24 months of orders by ship-to state from every channel.
- Separate marketplace sales from your own storefront sales.
- Compare each state's totals with its current threshold rules on the department of revenue website.
- Register where required, set up calculation, and calendar every filing date.
- Review past exposure with a tax professional and consider VDAs where needed.
If you're reviewing your online payment setup, MannyPay offers gateway options that connect to Shopify, WooCommerce and QuickBooks. Request a free quote and a MannyPay specialist will respond within one business day.
This article is for general educational purposes and is not legal, tax or financial advice. Card network rules and state laws change; confirm current requirements for your business.
