Marketplace Facilitator Exemption Doesn't Erase Physical Nexus: What $1M Amazon Sellers Still Owe Directly
You sell $1M annually on Amazon. Amazon collects and remits sales tax on every marketplace order. You assume your sales tax obligations are handled. They're not. Your FBA inventory is stored in warehouses across 6 states. That inventory creates physical nexus — and marketplace facilitator laws don't touch it. You still need to register in those states, and if you also sell through your own Shopify store, you owe tax on every direct sale shipped into those states. Here's how the dual-track obligation works and where sellers are getting audited for ignoring it.
Key Takeaways
- • Marketplace facilitator laws shift remittance of marketplace sales to the platform, not all sales tax obligations: Amazon collects on Amazon sales only — not on your Shopify, wholesale, or direct-to-consumer sales
- • FBA inventory creates physical nexus that survives marketplace facilitator coverage: Your inventory in an Amazon warehouse is your property in that state, period
- • Registration is still required: Most states require a sales tax permit even when Amazon handles marketplace remittance — the permit is tied to nexus, not to who collects
- • PA, WA, and CA have actively audited FBA sellers who failed to register: These states cross-reference Amazon fulfillment center locations with their registration databases
- • The dual-track model is non-negotiable: Marketplace sales handled by Amazon + direct sales handled by you, even in the same state, even in the same month
The Business: A $1M Amazon Seller with FBA Inventory in 6 States
Meet the Seller
PeakGear is an outdoor accessories brand selling primarily through Amazon FBA. The founder operates from a home office in Austin, Texas. Annual revenue: $1,000,000 — roughly $850,000 through Amazon and $150,000 through a Shopify store. No employees outside Texas. No office space in other states. But Amazon's inventory placement algorithm has distributed PeakGear's FBA inventory across warehouses in 6 states: Texas (home), California, Pennsylvania, Georgia, New Jersey, and Washington.
PeakGear's founder believes the sales tax situation is simple: Amazon collects on the $850K in marketplace sales, so those are covered. The $150K Shopify store only triggers economic nexus in Texas (home state). Everything else is handled.
This belief is wrong in at least 5 states. Here's why.
What Marketplace Facilitator Laws Actually Do — and Don't Do
Every U.S. state with a sales tax has enacted marketplace facilitator laws. These laws shift the responsibility for collecting and remitting sales tax on marketplace transactions from the third-party seller to the marketplace platform — Amazon, Etsy, Walmart Marketplace, and others.
The key phrase is "on marketplace transactions." The law addresses who collects on sales made through the platform. It does not:
- Eliminate your physical nexus created by inventory, employees, or property in a state
- Remove your obligation to register for a sales tax permit in states where you have nexus
- Cover sales made through your own website, wholesale channels, or any non-marketplace channel
- Prevent states from auditing you for compliance failures on direct sales
Think of marketplace facilitator status as a collection agent for one channel. It handles Amazon sales. Everything else — your Shopify store, your wholesale orders, your direct invoices — remains your responsibility.
FBA Inventory = Physical Nexus, Regardless of Who Collects
When Amazon stores your inventory in a fulfillment center, that inventory is your property sitting in that state. Under longstanding physical nexus doctrine, tangible personal property stored in a state creates nexus for the owner. This was true before Wayfair, before marketplace facilitator laws, and it remains true now.
Amazon's FBA program creates physical nexus in every state where your inventory is stored. The marketplace facilitator law in that state means Amazon collects on sales made through Amazon. But the physical nexus from your inventory creates a separate, independent obligation: you must register for a permit, and you must collect on any non-marketplace sales into that state.
| State | FBA Inventory? | Physical Nexus? | Amazon Collects on Marketplace Sales? | PeakGear Must Collect on Shopify Sales? | Registration Required? |
|---|---|---|---|---|---|
| Texas | Yes | Yes | Yes | Yes | Yes |
| California | Yes | Yes | Yes | Yes | Yes |
| Pennsylvania | Yes | Yes | Yes | Yes | Yes |
| Georgia | Yes | Yes | Yes | Yes | Yes |
| New Jersey | Yes | Yes | Yes | Yes | Yes |
| Washington | Yes | Yes | Yes | Yes | Yes |
Every row tells the same story: FBA inventory creates physical nexus, Amazon collects on marketplace sales, but PeakGear is still on the hook for Shopify sales and must hold an active permit. The marketplace facilitator law handles one column. Physical nexus fills the rest.
Off-Platform Sales: The Gap Marketplace Facilitator Laws Don't Cover
PeakGear does $150,000 annually through its Shopify store. Shopify is not a marketplace facilitator. It's a shopping cart platform. It doesn't collect or remit sales tax on PeakGear's behalf (unless PeakGear configures it to do so).
This means every Shopify order shipped to a customer in California, Pennsylvania, Georgia, New Jersey, or Washington — states where PeakGear has physical nexus through FBA inventory — requires PeakGear to collect and remit sales tax directly. Amazon's facilitator status is irrelevant. The sale didn't happen on Amazon.
PeakGear's Shopify Exposure by State
With $150K in annual Shopify revenue distributed across all 50 states, here's the approximate exposure in the 6 FBA inventory states:
- • California: ~$18,000 in Shopify sales × up to 10.25% combined rate = ~$1,845 in uncollected tax
- • Pennsylvania: ~$9,500 in Shopify sales × 6% state rate = ~$570 in uncollected tax
- • Washington: ~$7,200 in Shopify sales × up to 10.25% combined rate = ~$738 in uncollected tax
- • Georgia: ~$6,800 in Shopify sales × up to 8.9% combined rate = ~$605 in uncollected tax
- • New Jersey: ~$6,100 in Shopify sales × 6.625% rate = ~$404 in uncollected tax
- • Texas: ~$11,400 in Shopify sales × up to 8.25% combined rate = ~$941 in uncollected tax
Total annual exposure: ~$5,103 in uncollected sales tax. Add interest, penalties, and a multi-year lookback period, and the liability grows to $15,000-$25,000+ depending on how long the seller has been non-compliant.
This isn't theoretical. PeakGear's founder assumed Amazon's marketplace facilitator status covered everything. It covered $850K in Amazon sales. The $150K Shopify channel was generating uncollected tax liability every single month in 6 states.
The Registration Requirement: Why "Amazon Collects" Isn't Enough
Even if PeakGear had zero off-platform sales — even if every dollar flowed through Amazon — the registration problem remains. Physical nexus through FBA inventory means PeakGear is required to hold an active sales tax permit in each of those 6 states.
Why does registration matter if Amazon is already collecting? Three reasons:
- State law requires it. Most states tie the registration requirement to nexus status, not to collection activity. Having nexus = must register. Whether someone else collects on your behalf is a separate question.
- Filing requirements may still apply. Some states require registered sellers to file returns even if remittance is $0 because a marketplace facilitator handled collection. Missing a zero-dollar return can trigger penalties and late-filing notices.
- Audit exposure. An unregistered seller with known physical presence in a state is a target. States can — and do — assess penalties for failure to register, separate from any tax owed.
The registration requirement exists because physical and economic nexus create independent obligations. Marketplace facilitator laws address the collection side of economic nexus for marketplace sales. They do not address the registration side of physical nexus.
States Where Failure to Register Has Triggered Audits
Three states have been particularly aggressive in auditing Amazon FBA sellers who failed to register despite having inventory in-state:
- Pennsylvania: Pennsylvania's Department of Revenue has sent nexus questionnaires directly to Amazon FBA sellers identified through fulfillment center records. The state cross-references Amazon warehouse locations (there are multiple major FBA facilities in Pennsylvania) with its sales tax registration database. Sellers with inventory in PA warehouses who aren't registered receive inquiry letters. Pennsylvania's 6% flat rate makes the per-seller exposure modest, but the state pursues registrations aggressively — and the penalties for failure to register add up.
- Washington: Washington was one of the first states to enact marketplace facilitator legislation and one of the most aggressive in enforcing physical nexus from FBA inventory. The Department of Revenue has flagged unregistered sellers with inventory in Washington fulfillment centers. Washington also imposes B&O tax on business activity in the state, adding a second compliance layer that marketplace facilitator laws don't address.
- California: The CDTFA has asserted physical nexus against out-of-state sellers based on FBA inventory stored in California warehouses. With Amazon operating over a dozen major fulfillment centers in California, the state has a large pool of potentially non-compliant sellers. California's combined state and district tax rates can exceed 10%, making the back-tax exposure significant even on modest Shopify revenue.
These aren't isolated incidents. As states become more sophisticated in identifying FBA sellers with in-state inventory, expect enforcement activity to expand. The data is readily available — Amazon publishes fulfillment center locations, and states can request inventory placement data during audits.
The Dual-Track Compliance Model
The correct approach for any seller using FBA alongside direct sales channels is a dual-track model:
| Sales Channel | Who Collects Sales Tax? | Who Remits Sales Tax? | Seller's Responsibility |
|---|---|---|---|
| Amazon Marketplace | Amazon (as marketplace facilitator) | Amazon | Register for permits; file returns (some states require $0 returns) |
| Shopify / Own Website | Seller | Seller | Register, collect, file, and remit in all nexus states |
| Etsy / Walmart Marketplace | Platform (as marketplace facilitator) | Platform | Register for permits; file returns as required |
| Wholesale / B2B Direct | Seller | Seller | Collect exemption certificates; remit on non-exempt sales |
For PeakGear, this means configuring Shopify to collect sales tax in all 6 FBA inventory states, registering for permits in each state, and filing returns that account for both marketplace-facilitated sales (reported separately or as $0 depending on the state) and direct Shopify sales.
The dual-track model is not optional. It's not a conservative interpretation. It's what the law requires. Amazon handles track one. You handle track two. Ignoring track two because track one exists is how sellers end up in audit situations with multi-year back-tax exposure.
What This Means for Your Business
If you sell on Amazon FBA and have any off-platform sales channel, here are the practical steps:
- Identify every state where Amazon stores your inventory. Check your FBA inventory placement reports in Seller Central. Amazon's Inventory Event Detail report shows which fulfillment centers hold your stock. Each state on that list is a physical nexus state.
- Register for sales tax permits in all FBA inventory states. Don't wait for a notice. If you've been selling without registration, consider a voluntary disclosure agreement to limit lookback periods and waive penalties before the state contacts you.
- Configure your Shopify store (or other direct channel) to collect sales tax in those states. Shopify's built-in tax engine can handle this, but you need to enable it for the correct jurisdictions. Don't rely on Shopify's automatic economic nexus detection — your nexus is physical, and Shopify may not know about your FBA inventory.
- File returns on schedule, even if the amount is $0. Some states require returns from registered sellers regardless of whether tax was collected. A missed $0 return can trigger a penalty and an audit flag.
- Monitor inventory placement changes. Amazon moves inventory. A state where you had no inventory last quarter may have inventory this quarter. Check your placement reports monthly and update your nexus map accordingly.
Frequently Asked Questions
No. Amazon collects and remits sales tax on sales made through its marketplace, but this does not eliminate your physical nexus in states where you have FBA inventory. You are still required to register for a sales tax permit in those states, and you are responsible for collecting and remitting tax on any sales made outside the Amazon marketplace — including your own Shopify store, wholesale orders, or any other direct sales channel.
Last Updated: May 6, 2026
Disclaimer: This information is provided for educational and informational purposes only and does not constitute tax, legal, or financial advice. Tax laws and regulations change frequently. While we strive to keep this information accurate and up-to-date, we make no representations or warranties of any kind about the completeness, accuracy, reliability, or suitability of this information. Please consult with a qualified tax professional or attorney for advice specific to your business situation. Always verify current requirements with the official state tax authority.