What's the difference between economic nexus and physical nexus?
Physical nexus and economic nexus both create the same sales tax registration obligation, but through different triggers: physical nexus from tangible presence in a state, economic nexus from crossing a sales threshold. Six dimensions distinguish how each is created, measured, and resolved, summarized below.
| Dimension | Physical nexus | Economic nexus |
|---|---|---|
| What creates it | Tangible presence: inventory, employees, contractors, offices, owned property, trade-show activity. | Sales of tangible personal property delivered into the state above a dollar threshold (and in some states a transaction count). |
| How it's measured | Existence of the activity. One employee or one warehouse pallet can be sufficient. | Cumulative gross or taxable receipts (varies by state) across a measurement window. Some still include a transaction count. |
| When it triggers | The day the activity begins. | The day cumulative sales cross the threshold within the measurement window. |
| Lookback shape | From the date physical presence began. | From the threshold-crossing date, bounded by the measurement window. |
| Registration timing | Generally before the next taxable transaction. | State-specific. Texas requires permit and collection by the first day of the fourth month after the threshold month (Tex. Tax Code §151.107). |
| Deregistration shape | Available once presence ends, subject to trailing-nexus rules. | Available once sales drop below the threshold for the required period. Trailing rules are explicit in a few states, silent in most. |
What creates physical nexus for an ecommerce brand
Physical nexus is the older concept and the one most likely to catch an ecommerce brand off guard. Wayfair (2018) overruled the Quill (1992) physical-presence bright line only to authorize economic nexus, but it did not remove physical nexus, which every sales tax state still asserts through "engaged in business" provisions (Cal. Rev. & Tax. Code §6203; Tex. Tax Code §151.107).
For a mid-market ecommerce brand, the triggers a finance team actually encounters are:
- Inventory at a third-party warehouse or 3PL. Pallets in a Flexport or ShipBob facility, or in a brand-owned warehouse, create physical nexus in that state.
- Amazon FBA inventory. Amazon places inventory across fulfillment centers without seller control. Historically treated as nexus everywhere; the Pennsylvania Commonwealth Court ruled the opposite in Online Merchants Guild v. Hassell (2022). State-specific and unsettled outside Pennsylvania.
- Remote employees. A single W-2 employee in a state generally creates physical nexus there.
- Contractors and 1099s. Many states treat in-state independent contractors as nexus-creating, especially when sales-related.
- Offices, retail locations, and pop-ups. Any leased or owned commercial space in the state.
- Trade shows and temporary activity. Several states (Illinois, New York, California) treat a threshold of trade-show days as nexus triggers.
- Owned tangible property. Equipment, fixtures, or other property stationed in the state.
Each trigger operates independently of sales volume. Having one employee in Massachusetts is enough to create physical nexus on its own.
Most mid-market ecommerce brands run these triggers on top of Shopify, where Shopify Tax handles checkout calculation and direct-Shopify nexus signals well. What it does not see is the list above: 3PL inventory, FBA placements, remote hires, and off-Shopify volume on Amazon, Walmart, and TikTok Shop. Each of those still has to be tracked and registered separately, regardless of what's handling checkout.
What economic nexus is, and what the Wayfair ruling changed
Economic nexus is the trigger that emerged after 2018: state authority to require a remote seller to register and collect tax based on sales volume alone, with no physical presence required. The authorizing case is South Dakota v. Wayfair, Inc., 138 S. Ct. 2080 (2018). South Dakota's own law set the original template: $100,000 in sales OR 200 separate transactions delivered into the state over the current or preceding calendar year.
The overruled cases were Quill Corp. v. North Dakota, 504 U.S. 298 (1992) and National Bellas Hess, Inc. v. Department of Revenue of Illinois, 386 U.S. 753 (1967).
Both held that the dormant Commerce Clause barred states from compelling remote sellers without physical presence to collect. Wayfair held that economic and virtual contacts can establish the substantial nexus the Commerce Clause requires.
Almost every sales tax state adopted economic nexus within three years; Florida (effective July 1, 2021; TIP 21A01-03) and Missouri (effective January 1, 2023) were the last.
Once a brand triggers economic nexus, the work begins. US sales tax operates at the state level plus thousands of local jurisdictions: county, city, special district, transit authority, business improvement district. A single transaction in Cook County, Illinois carries rate components from the state, the county, the City of Chicago, and the Regional Transportation Authority. That rolls up to 13,000+ active sales tax jurisdictions nationwide. Correct checkout calculation means resolving the buyer's address against that map.
Modern providers do this through a single API call against pre-computed rate tables; TaxCloud calculates across all 13,000+ jurisdictions through one integration, letting a brand register across dozens of states without proportionally growing the work.
How thresholds vary across states in 2026
Wayfair authorized economic nexus but did not dictate the threshold. Each state set its own. Six structural variations matter:
- The $100,000 default. Most states set this over the measurement window: Florida, Pennsylvania, Massachusetts, Washington, Illinois, Tennessee.
- The $500,000 high-volume states. California (Cal. Rev. & Tax. Code §6203), New York (NY Tax Law §1101(b)(8)), and Texas (Tex. Tax Code §151.107).
- The $250,000 mid-tier states. A small group, including Alabama and Mississippi.
- AND tests vs. OR tests. Most dual-threshold states use OR. New York uses AND.
- Gross vs. taxable vs. retail measurement. Texas counts total revenue including exempt sales; Florida counts only taxable remote sales; Washington counts cumulative gross receipts including facilitated sales. Reading "$100,000" the same way across states is a category error.
- The transaction-count removal trend. As of 2026, thirteen states have removed the 200-transaction test: California, Washington, South Dakota, Indiana, North Carolina, Wyoming, Maine, Louisiana, Alaska, Utah, Illinois (effective January 1, 2026 via P.A. 104-0006), North Dakota (effective for taxable years after December 31, 2018 via SB 2191), and Wisconsin (effective February 20, 2021). The 2018 default of "$100k or 200 transactions" is stale at high volume. Tennessee separately lowered its threshold from $500,000 to $100,000 effective October 1, 2020.
The New York AND test
New York requires both $500,000 in cumulative gross receipts AND more than 100 sales transactions, measured over the immediately preceding four sales tax quarters (NY Tax Law §1101(b)(8); NY DTF guidance, last updated May 30, 2025). This is an AND test where most dual-threshold states use OR. Misreading the conjunction has produced real audit exposure.
The table below covers eight representative states.
| State | Threshold | Measurement basis | Lookback | Statute |
|---|---|---|---|---|
| CA | $500,000 | TPP delivery, incl. related persons (IRC §267(b)) | Preceding or current calendar year | RTC §6203; AB 147 (2019) |
| NY | $500,000 AND > 100 transactions | Cumulative gross receipts (incl. exempt) | Preceding 4 sales tax quarters | Tax Law §1101(b)(8) |
| TX | $500,000 | Total Texas revenue (taxable + nontaxable + exempt) | Preceding 12 months | Tax Code §151.107; 34 TAC §3.286 |
| FL | $100,000 | Taxable remote sales | Previous calendar year | SB 50 (2021); Fla. Stat. §212.0596 |
| IL | $100,000 | Gross receipts from sales of TPP | Preceding 12 months, quarterly determination | 35 ILCS 185; P.A. 104-0006 (200-tx test removed eff. 1/1/2026) |
| PA | $100,000 | Gross sales (all channels) | Calendar year (4/1 to 3/31 collection cycle) | Act 13 of 2019 |
| MA | $100,000 | MA sales | Previous calendar year | 830 CMR 64H.1.9 |
| WA | $100,000 | Cumulative gross receipts (incl. facilitated, exempt) | Current or preceding calendar year | RCW 82.08.052 |
How the two interact when a brand triggers both
The two triggers are independent paths to the same destination. Whichever lands first creates the registration obligation; the second adds no new obligation but can shift the lookback shape and retrospective exposure.
A common pattern at $10M to $100M: a brand crosses California's $500,000 economic threshold (Cal. Rev. & Tax. Code §6203) on direct Shopify volume, registers, and begins collecting. Six months later, a 3PL adds a California node. Physical nexus now exists, but registration is already in place and nothing new is owed prospectively. Retrospectively, the question differs. If physical presence had existed before economic nexus was triggered, the lookback runs from the date physical presence began, not the threshold-crossing date. In high-rate states, that adds years of uncollected tax to audit exposure.
The inverse surprises brands: physical nexus that pre-dates economic-nexus crossing and was never registered. A remote hire in Washington in 2021, never reported, plus economic-nexus crossing in 2024. Three years of unregistered exposure accumulate in a state that counts gross receipts broadly (RCW 82.08.052) and routinely contests deregistration claims. The remediation path is not standard registration but a voluntary disclosure agreement that caps lookback and waives penalties in exchange for full disclosure.
In short: economic nexus drives most multi-state registrations at this scale; direct-channel volume crosses thresholds before footprint expands. Physical nexus is what catches brands by surprise.
What this means operationally for a $10M to $100M ecommerce brand
A $10M to $100M ecommerce brand on Shopify typically lives with both nexus types active across 25 to 40 states. The number depends on product mix (taxability varies), channel mix (Amazon, Walmart, and TikTok Shop volume affects the brand's threshold differently by state), and physical footprint (3PLs, FBA, remote hires).
The question shifts. It is no longer "do we have nexus?" but "where, when, and with what documentation?" Three operational consequences follow.
First, the math on filing volume is not what it appears. The Streamlined Sales Tax (SST) program is a multistate compact among 23 full member states, plus Tennessee as an associate member, that consolidates filing into a single process when the brand works with one of the program's Certified Service Providers.
For a brand registered in 30 states, that means one filing covering the 24 SST states plus six filings for the rest. TaxCloud is one of those CSPs, and SST states cover filing costs for the 24.
Second, nexus is a monitoring problem, not a one-time analysis. Thresholds measure against a moving window; the footprint changes with each new 3PL, remote hire, or marketplace channel. The cadence that holds at $10M to $100M is monthly threshold tracking by state plus quarterly footprint reviews.
Third, the contested questions (FBA inventory, entity-level vs. consolidated measurement, trailing nexus) are recurring decisions at scale, not edge cases. Each needs a documented position, defensible at audit, refreshed as guidance shifts.
The question is what the operating model looks like at a 30-state steady state. TaxCloud is built for that: 13,000+ jurisdictions through one API, consolidated SST filing across the 24 member states, and the documentation trail for audit defense.