Amazon FBA Sales Tax: When Stored Inventory Creates Nexus

TL;DR

FBA inventory that Amazon stores in a state creates physical nexus there — there is no dollar threshold, so a single unit is enough. But marketplace facilitator laws now cover every US state with a sales tax, so Amazon calculates, collects and remits the tax on your Amazon sales. For a seller who sells only on Amazon, that nexus rarely turns into a return to file — although a few states still make you register. Your own Shopify sales are a separate story, and they stay yours.

Nexus and a filing obligation are two different things

This is the distinction the internet gets wrong, and it is the whole article.

Having nexus in a state means the state can impose a tax duty on you. It does not mean you automatically owe a return. These are two separate steps, and marketplace facilitator laws sit between them. Skip the second step and you get the seller-forum panic — “I have nexus in 27 states, I’m doomed” — which is almost never the real position.

After South Dakota v. Wayfair (decided June 21, 2018), a state can require a remote seller to collect based on economic activity alone — no office, no staff, no warehouse. That overturned the old physical-presence rule from Quill, but it did two things at once: it opened economic nexus and confirmed that physical presence still creates nexus the old-fashioned way. FBA inventory is the physical kind.

How FBA inventory creates physical nexus

Inventory stored in a state is a classic physical presence, and physical nexus carries no threshold. Where economic nexus needs a sales figure to trip it — commonly $100,000 a year as of 2026, though the figure varies by state and changes — physical nexus can be triggered by a single unit sitting in a fulfillment center, regardless of how much you sell into that state.

The complication genuinely unique to FBA: you do not control where your inventory goes. Amazon distributes and redistributes your stock across its network to shorten delivery times, and it does not ask permission. Ship one pallet to a single intake center and you can wake up with inventory spread across a dozen states — physical nexus in fifteen to thirty states across a mature footprint, none of it a decision you consciously made.

If FBA nexus stopped there, the panic would be justified. It does not stop there.

Why the facilitator laws take most of the sting out

Marketplace facilitator laws moved the collection duty off the seller and onto the platform — and as of 2026 every state that has a sales tax has one. Missouri was the last to adopt one, effective January 1, 2023; before that the map had holes, which is why older advice reads as more alarming than today warrants. (For orientation, 45 states plus Washington, D.C. levy a statewide sales tax; the five “NOMAD” states — New Hampshire, Oregon, Montana, Alaska and Delaware — have none.)

Under these laws, Amazon is the party that calculates, collects and remits the sales tax on your marketplace sales. The tax on your Amazon transactions is Amazon’s responsibility to send to the states. So even in a state where FBA inventory unquestionably gave you physical nexus, the tax on your Amazon sales into that state is already being handled — not by you.

That is the crucial nuance: nexus does not equal an automatic return when the facilitator is doing the remitting. For a seller whose only US channel is Amazon, physical nexus in twenty states frequently means twenty states where there is little or nothing left to file.

Registration is still a separate question

“Amazon remits” is not the same as “you have nothing to do.” Whether you must register — and whether you must file a return even when the tax owed is zero — varies by state, and this is where a marketplace-only seller can still have a small amount of work.

The three patterns you will meet:

• No registration required. Some states do not make a marketplace-only seller register at all. Pennsylvania, for example, does not require a remote marketplace seller to register even after crossing the economic threshold, as long as every sale runs through a collecting marketplace.
• Register and file, but net to zero. Washington requires marketplace sellers over its $100,000 threshold to register and file, reporting the gross sales and then deducting the facilitated portion — the sales-tax line often lands at zero, but a return is still due.
• Already registered means keep filing. If you hold an active permit in a state, that state generally still wants a return, even if it is a zero return covering only facilitated sales.

The Streamlined Sales Tax guidance says the quiet part plainly: a marketplace seller “may also be required to register and file returns” depending on the state. There is no single national answer — you confirm it state by state. This is exactly the kind of per-state review our sales tax registration and returns service is priced around, so you pay only where an obligation actually exists. For the income-tax side of the same FBA footprint, see Amazon FBA and ETBUS for non-residents.

The Pennsylvania case, and why the fear is overblown

A court has already pushed back on the most aggressive reading of FBA nexus. In Online Merchants Guild v. Hassell (Pennsylvania Commonwealth Court, No. 179 M.D. 2021, September 9, 2022), the court held that FBA sellers whose only Pennsylvania contact was Amazon-stored inventory did not have sales-and-use-tax or personal-income-tax nexus, reasoning that a seller has no control over where Amazon places the stock.

Do not over-read it: one state, still an outlier. Most states treat stored inventory as physical nexus, and you should assume that by default. But it is a useful antidote to the fear-mongering — even the state that mailed roughly 11,000 questionnaires to FBA sellers lost in court, and the states pursuing this are far fewer, and far less successful, than the “you owe back tax in 30 states” content implies.

Your own Shopify sales are still yours

The facilitator shield only covers the marketplace. Sell the same product through your own Shopify storefront and you are the merchant of record for those sales — Shopify Tax calculates and collects, but does not register you or file anything. And the FBA inventory that gave you physical nexus applies to those off-Amazon sales too. So an FBA seller who also runs a Shopify store has the most involved position here: nexus that is real, physical, and now attached to sales nobody else is remitting. The foreign-seller Shopify vs Amazon guide walks through that split.

How to see which states hold your stock

You cannot assess FBA nexus from memory — you pull the report. In Amazon Seller Central, go to Reports → Fulfillment → Inventory Ledger (the menu location as of 2026; Amazon moves things around). It works like a bank statement for your inventory, showing movement by fulfillment center — which tells you which states physically hold your stock. That list is your physical-nexus map. Cross-reference it against the state-by-state nexus rules and your off-Amazon sales, and the picture of what you actually need to do — usually far less than feared — comes into focus.

An honest limitation

Multi-state sales tax registration and filing is a specialist discipline with its own software, its own registrations and its own recurring filings. It is not an add-on to a federal engagement, and deep 50-state registration work belongs with a dedicated sales tax specialist.

What a federal-focused practice can do is tell you which questions are actually yours: separating the FBA sales-tax question from the ETBUS income-tax question from the Form 5472 question, so you are not paying to register in twenty states when the facilitator laws require nothing of you in most of them.

Frequently Asked Questions

Q: I sell only on Amazon with FBA. Do I owe back sales tax in every state my inventory touched? A: Almost certainly not the way the forums describe. Amazon has been collecting and remitting on your marketplace sales under facilitator laws that now cover every sales-tax state. Physical nexus exists where your inventory sits, but that mostly becomes a registration question in a handful of states, not a pile of unpaid tax.

Q: Amazon remits the tax — so I can ignore sales tax entirely? A: Not quite. Collection is handled for Amazon sales, but some states still require a marketplace-only seller to register and file a (often zero) return. And any sales you make off Amazon are entirely yours to handle.

Q: Does the Pennsylvania FBA case mean stored inventory never creates nexus? A: No. Online Merchants Guild v. Hassell applies to Pennsylvania and remains an outlier. Treat stored inventory as creating physical nexus by default elsewhere, and rely on the facilitator laws — not the case — to keep most of it from turning into a filing.

Q: How do I find where my FBA inventory is stored? A: Use the Inventory Ledger report in Seller Central under Reports → Fulfillment → Inventory Ledger. It reports inventory by fulfillment center, so you can map your physical nexus from real data rather than guesswork.

Next Steps

Most FBA sellers who ask about sales tax arrive convinced they owe returns in dozens of states, and most of them do not — the facilitator laws did their job. The productive first move is to separate the questions: pull your Inventory Ledger to see where nexus physically sits, confirm which of those states require a marketplace-only seller to register, and keep your off-Amazon sales in a separate bucket. Once that is measured, the real work is usually small, and often nothing.

Sources

• U.S. Supreme Court Issues Decision in South Dakota v. Wayfair — decided June 21, 2018, overruling Quill’s physical-presence rule (Sales Tax Institute) (accessed 2026-09)
• Marketplace Facilitator Laws (Tax Foundation) (accessed 2026-09)
• Missouri, the final state to enact Wayfair marketplace laws — effective January 1, 2023 (TaxJar) (accessed 2026-09)
• State and Local Sales Tax Rates, Midyear 2026 — 45 states plus D.C. have a statewide sales tax (Tax Foundation) (accessed 2026-09)
• Economic Nexus State Guide — thresholds by state (Sales Tax Institute) (accessed 2026-09)
• What Is Physical Nexus? Inventory storage and no-threshold physical nexus (TaxCloud) (accessed 2026-09)
• Online Merchants Guild v. Hassell, No. 179 M.D. 2021 — Commonwealth Court of Pennsylvania opinion, September 9, 2022 (Unified Judicial System of Pennsylvania) (accessed 2026-09)
• Fulfilled-By-Amazon Sellers Successful Against Pennsylvania for Inventory Nexus — roughly 11,000 sellers received questionnaires (Ryan) (accessed 2026-09)
• Pennsylvania: Remote Sales via Amazon FBA Did Not Create Nexus (BDO) (accessed 2026-09)
• Pennsylvania marketplace facilitator law — registration for marketplace sellers (TaxJar) (accessed 2026-09)
• Marketplace sellers — registration and filing (Washington Department of Revenue) (accessed 2026-09)
• Marketplace Facilitator guidance for businesses (Streamlined Sales Tax Governing Board) (accessed 2026-09)
• Inventory Ledger report — Seller Central help reference, found under Reports → Fulfillment → Inventory Ledger (Amazon Seller Central) (accessed 2026-09)

This article is general information, not tax advice. State sales tax rules vary and change frequently — confirm the current rule for any state before acting.