Economic Nexus for E-Commerce Startups: When Selling Into Another State Creates a Sales Tax Bill

An ecommerce startup can create sales-tax obligations in a state without an office, employee, or other traditional physical presence once its sales meet that state’s economic-nexus threshold. The threshold, sales base, measurement period, and marketplace treatment vary by state, so confirm the trigger and register as required before beginning collection.

Thresholds and procedures verified as of September 2026.

Question	Short Answer
Can I create nexus without an office?	Yes. Wayfair removed physical presence as an absolute constitutional requirement.
Is there one national nexus threshold?	No
Is $100,000 common?	Yes, but the sales counted toward it vary
Do all states still use 200 transactions?	No
Do marketplace sales matter?	State-specific
Does marketplace collection cover my direct site?	No
Should I register once I trigger nexus?	Follow that state’s current registration and collection timing rule
What if I am already late?	Model historical exposure before choosing a remediation path

For a lean ecommerce team, economic nexus works best when it becomes part of a broader startup regulatory compliance process: measure state activity, separate marketplace and direct sales, identify triggers, register correctly, configure checkout, file returns, and reassess exposure every quarter.

Economic Nexus for an Ecommerce Startup: The Rule in Plain English

Economic nexus means a state can require a remote seller to collect and remit sales tax based on its economic activity in that state even when the seller lacks traditional physical presence there. Each state defines its own threshold and calculation rules.

Nexus simply means a sufficient connection with a state for that state to impose a tax-related obligation. Economic nexus is only one way that connection can arise.

Nexus Type	Typical Trigger
Physical nexus	Property, employees, inventory, or other in-state presence
Economic nexus	State-defined sales or activity threshold
Marketplace-related obligation	Depends on facilitator law and seller facts
Other nexus	Affiliate, click-through, trade-show, inventory, or other state rules where applicable

This is not an exhaustive list of every nexus theory. A business can have physical nexus even while remaining below a state’s economic-nexus threshold.

What South Dakota v. Wayfair Changed for Online Sellers

South Dakota v. Wayfair, Inc. removed the old rule that physical presence was always necessary before a state could require an out-of-state seller to collect sales tax. 

In South Dakota v. Wayfair, Inc., decided June 21, 2018, the U.S. Supreme Court overruled the physical-presence rule associated with Quill and Bellas Hess, removing physical presence as an absolute constitutional prerequisite for this type of state sales-tax collection obligation.

The Court considered South Dakota’s then-current law, which used $100,000 of sales or 200 transactions. It did not create those numbers as a nationwide standard.

The operational result is straightforward: shipping nationwide now requires testing each destination state’s current remote-seller law instead of asking only, “Do we have an office there?”

Wayfair Economic Nexus Thresholds Are Not the Same in Every State

Wayfair economic nexus thresholds differ not just in dollar amount, but in what sales count, when they are measured, and whether transaction counts or marketplace sales matter.

Four variables deserve particular attention:

• Revenue threshold: $100,000 appears frequently, but higher thresholds and different definitions exist.
• Transaction-count threshold: Some states retain a transaction test; others have repealed theirs.
• Sales base: A state may use gross sales, retail sales, taxable sales, tangible-personal-property sales, or another defined base.
• Measurement period: The test may use the current calendar year, previous year, current or previous year, preceding 12 months, or another state-defined period.

Marketplace treatment creates another layer. California and Texas, for example, generally include facilitated marketplace sales when applying the seller’s economic-nexus calculation, while Georgia permits a remote marketplace seller to exclude qualifying facilitated sales from its own threshold calculation.

Why “$100,000 in Sales” Is Only a Starting Point

A $100,000 headline is useless unless you know what the state means by “sales.” Threshold analysis begins with the statutory or agency definition, not the number in a spreadsheet column.

Consider a hypothetical startup with $125,000 of customer sales into State A:

• $80,000 through its own site;
• $45,000 through a marketplace.

If State A counts all applicable marketplace and direct sales, its threshold-sales figure could be $125,000. If its rule excludes qualifying marketplace-facilitated sales for the seller, the relevant amount could instead be $80,000.

The same problem applies to exempt transactions, wholesale orders, services, and other revenue categories. Always read the state’s threshold definition.

The 200 Transactions Threshold Is Disappearing in Many States

The old “$100,000 or 200 transactions” shortcut is no longer a reliable compliance rule. The 200-transaction concept came from the South Dakota statute reviewed in Wayfair, but states have since moved in different directions.

South Dakota itself shows why old Wayfair charts age badly: the state’s Department of Revenue confirms that South Dakota removed the 200-transaction remote-seller test effective July 1, 2023, leaving its sales-based test as the relevant economic-nexus criterion. 

Wisconsin eliminated its test effective February 20, 2021, and Illinois removed its 200-transaction threshold effective January 1, 2026. 

Georgia still uses a 200-transaction alternative, while New York currently uses a different transaction test: more than 100 sales and more than $500,000 of gross receipts.

That makes 200 transactions threshold repeal research a recurring compliance task rather than a one-time setup.

Representative state rules

State	Current Dollar Test	Transaction Test Still Applies?	Sales Base	Measurement Period	Primary Source
California	Exceeds $500,000	No	TPP delivered into California; seller threshold includes marketplace-facilitated sales	Current or prior calendar year	CDTFA
Texas	Exceeds $500,000	No	Total Texas revenue, including taxable and nontaxable sales and marketplace sales	Preceding 12 calendar months	Comptroller
Florida	Exceeds $100,000	No	Taxable remote sales; qualifying marketplace-facilitated sales are excluded from the marketplace seller’s own test	Previous calendar year	Florida DOR
Illinois	$100,000 or more	No, effective Jan. 1, 2026	Cumulative gross receipts from applicable TPP sales	Preceding 12 months, tested quarterly	IDOR
South Dakota	Exceeds $100,000	No; repealed July 1, 2023	Gross sales, including products, electronically delivered products, and services	Previous or current calendar year	South Dakota DOR
Wisconsin	Exceeds $100,000	No; repealed Feb. 20, 2021	Gross sales, including taxable and nontaxable sales	Previous or current calendar year	Wisconsin DOR
New York	Exceeds $500,000	Yes: more than 100 sales, with both tests required	Gross receipts from TPP delivered into New York, including taxable and exempt sales	Immediately preceding four sales-tax quarters	NY Tax Department
Georgia	Exceeds $100,000	Yes: 200 or more retail sales as alternative test	Applicable retail TPP sales; qualifying facilitated marketplace sales excluded for remote marketplace seller test	Previous or current calendar year	Georgia DOR

Representative states only. Thresholds and procedures verified as of September 2026. Old national charts should be treated as research leads, not current authority.

How to Measure Economic Nexus Before You Register

Measure nexus from transaction-level gross sales data, then adjust that data to each state’s threshold definition. Processor payouts and bank deposits are poor inputs because fees, reserves, refunds, settlement timing, and marketplace netting can distort sales.

Use this workflow:

1. Export orders by customer destination state.
2. Apply that state’s required measurement period.
3. Identify the categories included in its threshold sales base.
4. Separate direct-site and marketplace orders.
5. Tag taxable, exempt, wholesale, service, and other sales where relevant.
6. Calculate threshold sales using the state’s rule.
7. Compare the result with the current threshold.
8. Record the date the threshold was crossed.
9. Determine when registration and collection must begin.
10. Save the source, calculation, and supporting export.

A simple working tracker can look like this:

State	Direct Sales	Marketplace Sales	Threshold Sales Under State Rule	Transaction Count if Relevant	Current Threshold	Status
State A						Below
State B						Watch
State C						Triggered

Which Sales Count Toward Economic Nexus?

There is no universal answer. A state’s calculation may include taxable sales, exempt sales, wholesale transactions, marketplace sales, services, digital products, or other receipts—or exclude some of them.

California’s $500,000 test includes total sales of tangible personal property delivered into California, including nontaxable transactions such as resale sales, and marketplace-facilitated sales count toward the marketplace seller’s threshold.

Florida uses a materially different approach for a remote marketplace seller: qualifying facilitated sales collected by the marketplace provider are not included when determining whether that seller’s non-marketplace remote sales exceed Florida’s threshold.

Read the state’s threshold definition, not just the headline dollar amount.

Marketplace Facilitator vs Direct Sales: Who Collects the Tax?

Startups that combine direct ecommerce with marketplace and platform-based business models need to separate two questions: does the seller have nexus in the state, and who is legally responsible for collecting tax on this particular transaction? 

A qualifying marketplace facilitator generally handles collection and remittance for transactions covered by that state’s facilitator law. Your Shopify, WooCommerce, or other direct storefront remains your responsibility when your own collection obligation applies.

Issue	Marketplace Sale	Direct Website Sale
Who calculates tax?	Depends on facilitator law/platform	Seller or seller’s tax system
Who collects/remits?	Often marketplace facilitator	Seller if collection obligation applies
Does sale count toward nexus threshold?	State-specific	Often relevant; verify state rule
Seller filing obligation	State-specific	Usually tied to seller’s registration
Records seller should retain	Marketplace reports	Orders, tax calculations, exemptions, refunds

California’s guidance is a useful illustration: marketplace-facilitated sales count in the economic-nexus calculation even though the facilitator may be responsible for the tax on those transactions.

Do Marketplace-Only Sellers Still Need to Register?

Sometimes yes and sometimes no. Marketplace collection does not create one national registration rule for marketplace-only sellers.

Texas says a remote marketplace-only seller generally does not need a Texas sales-tax permit when a certified marketplace provider collects on its behalf. California similarly provides relief in qualifying marketplace-only circumstances. 

South Dakota, by contrast, says a remote seller exceeding its threshold through marketplace sales may need to register even if it qualifies for non-filing treatment.

That is why “Amazon collects it for me” should never replace state-specific analysis.

Watch for Physical Nexus From Marketplace or Fulfillment Inventory

Economic nexus is not the only trigger. Inventory, employees, offices, warehouses, and some other in-state activities can create physical nexus before a revenue threshold is reached.

California, for example, states that inventory stored at an in-state third-party fulfillment center can cause a retailer to be engaged in business there.

Marketplace fulfillment therefore belongs in the same quarterly review as sales thresholds.

What Happens When You Cross an Economic Nexus Threshold?

Crossing a threshold starts a compliance sequence; it does not mean “turn on tax everywhere immediately.”

For each triggered state, determine:

1. exact crossing date;
2. legally required collection start date;
3. registration requirement;
4. product or service taxability;
5. applicable state and local sourcing;
6. filing frequency;
7. first return deadline;
8. zero-return requirements.

Timing varies substantially. California can require collection beginning when the threshold is crossed, while South Dakota requires registration by the first day of a month beginning at least 30 days after the threshold is met. Texas gives qualifying remote sellers until the first day of the fourth month after exceeding its safe harbor.

Sales Tax Registration by State: The Correct Sequence

Sales tax registration should be treated as part of the startup’s broader business licensing, tax registration, and financial-compliance process rather than a mass-registration reflex. Confirm the nexus trigger and required collection date before opening accounts state by state.

1. Confirm nexus.
2. Confirm the required collection start date.
3. Identify the administering agency.
4. Register directly or use an authorized multistate system where available.
5. Obtain the sales tax permit or account number.
6. Enable tax collection for applicable direct sales.
7. Test sourcing and product taxability.
8. Document marketplace treatment.
9. Calendar the first return.
10. Retain registration confirmations.

The Streamlined Sales Tax Registration System can provide one registration process for participating Streamlined states, but it does not cover every jurisdiction.

Do not casually add a checkout charge labeled “sales tax” before confirming registration and remittance requirements. Collecting money from customers without properly reporting and remitting it can create a separate compliance problem.

Registration Is Only the Beginning: Filing Frequency and Zero Returns

Registration normally creates an ongoing filing calendar. States can assign monthly, quarterly, annual, or other filing frequencies based on their own rules and account facts.

Wisconsin, for example, assigns remote-seller filing frequency based on registration information and taxable-sales volume and may later change it.

A period with no taxable direct sales does not automatically mean “nothing to file.” Some registered accounts require zero returns. Build deadlines from each state’s actual account notice rather than assumptions.

Configure Checkout Tax Collection by Destination

Checkout tax calculation should use the transaction’s applicable sourcing rule, product taxability, and jurisdiction—not a hard-coded statewide percentage.

For shipped orders, the delivery or ship-to address commonly matters under destination-based sourcing. Local jurisdictions can also matter; Texas, for example, generally bases a remote seller’s local use tax on the delivery location, subject to its optional single-local-rate regime.

Your checkout configuration should therefore preserve:

• complete delivery address;
• product tax category;
• exemption status;
• shipping taxability logic;
• direct-versus-marketplace channel;
• tax charged and jurisdiction;
• refunds and tax adjustments.

As the finance stack grows, connect tax configuration with broader rather than treating tax as a disconnected app setting.

Nexus Tells You Where to Register—Not Whether Every Product Is Taxable

Nexus answers where a collection obligation may exist. Taxability answers what is actually taxed.

Physical products, clothing, groceries, supplements, software, digital products, SaaS, and services can receive different treatment from one jurisdiction to another.

That means registration should trigger a product-taxability review before checkout goes live.

What If You Crossed the Threshold Months Ago and Never Registered?

A historical nexus problem should be quantified before it is “fixed.” Potential exposure can include uncollected tax, past-due returns, interest, penalties, and tax that is difficult or commercially unrealistic to recover from former customers.

Build a state-by-state exposure schedule showing the first nexus date, taxable direct sales, marketplace treatment, taxes that should potentially have been collected, and filing periods involved.

Do not register blindly before assessing past exposure

Standard registration may not always be the best first procedural step when several historical periods are unfiled.

Before contacting a state, investigate:

• first nexus date;
• historical direct and marketplace sales;
• applicable lookback;
• voluntary disclosure eligibility;
• possible penalty relief;
• whether prior state contact affects eligibility.

Material historical tax exposure can also become a cash-flow issue, so model it alongside the company’s broader .

Voluntary Disclosure Agreements When You Are Already Late

A voluntary disclosure agreement, or VDA, is a state-approved process that can allow an eligible taxpayer to resolve prior unfiled obligations under defined terms. Depending on the jurisdiction, those terms may include a limited lookback period and penalty relief while still requiring tax and usually interest.

Procedures are not uniform. The Multistate Tax Commission’s program, for example, coordinates disclosures with participating states and emphasizes that prior filings, payments, audits, or other contact can affect eligibility.

Situation	What to Investigate
Threshold crossed recently	Registration date and short-period exposure
Several years of direct sales	VDA eligibility and lookback
Marketplace-only historical sales	State-specific marketplace treatment
Prior state notice received	Whether VDA eligibility remains
Large tax exposure	CPA/SALT attorney review
Small isolated exposure	Cost-benefit of remediation options

A VDA does not erase the underlying tax, and there is no universal lookback period.

Marketplace facilitator laws also do not automatically eliminate historical exposure. Direct-site sales, pre-facilitator periods, transactions the marketplace did not cover, physical nexus, and registered-but-unfiled returns can still require review.

A Quarterly Economic Nexus Review a Two-Person Startup Can Actually Run

A quarterly nexus review works best as part of a broader compliance-management system for a growing business rather than a tax exercise performed once every December. Assign an owner, use a repeatable checklist, document decisions, and update the state-rule tracker whenever laws or sales channels change.

Step 1: Export sales by destination

Combine direct ecommerce, marketplaces, wholesale channels, and other order sources.

Step 2: Update the state-rule tracker

Record threshold, sales base, measurement period, transaction test, marketplace treatment, and current effective dates.

Step 3: Calculate threshold sales

Use gross order data adjusted to the state’s legal definition—not processor payouts.

Step 4: Classify states

Use operational statuses such as below threshold, approaching threshold, crossed, and registered.

Step 5: Review physical nexus

Check employees, inventory, fulfillment locations, warehouses, trade shows, and newly added operating activity.

Step 6: Act on triggered states

Confirm timing, register where required, configure checkout, and calendar the first return.

Step 7: Archive evidence

Save the sales export, state source, calculation, reviewer, and decision.

Sales tax compliance startup checklist

• Export sales by state
• Separate marketplace and direct sales
• Update threshold rules
• Check transaction-count tests
• Review physical nexus
• Flag states at 75–90% of threshold
• Confirm registrations
• Verify checkout tax settings
• Review first filing deadlines
• Save the quarterly nexus report

The 75–90% range is an internal monitoring control, not a statutory nexus threshold.

Simple startup nexus dashboard

State	Threshold Sales for Applicable Period	Current Threshold	% of Threshold	Marketplace Treatment Reviewed?	Registered?	Next Action
State A
State B
State C

Do not automatically use year-to-date sales for every state. The dashboard’s measurement period must follow the applicable state law.

[Expert insight opportunity: SALT professional explains why startups should track nexus quarterly instead of waiting until year-end, especially when marketplace and direct-site sales are growing at different rates.]

Example: A DTC Brand Goes From $20,000 to $2 Million in Nationwide Sales

A fictional DTC company can move from minimal multistate risk to several state obligations long before it builds a tax department.

In Year 1, the brand makes $20,000, mostly in its home state. In Year 2, marketplace sales accelerate, so the founders begin recording marketplace and direct transactions separately by destination.

By Year 3, nationwide revenue reaches $2 million. The quarterly export identifies State A as approaching its current threshold, State B as newly triggered under its state-specific calculation, and State C as already registered.

The team records State B’s crossing date, confirms its collection-start rule, registers, turns on destination-aware tax for taxable direct orders, and adds the state’s filing deadline to the close calendar.

During that review, the team discovers it crossed State D’s threshold several quarters earlier. Rather than blindly backdating registration, it models the direct-sales exposure and evaluates whether a VDA or another remediation process should be considered.

Common Economic Nexus Mistakes Ecommerce Startups Make

Common failures are operational rather than mathematical:

• assuming no office means no nexus;
• using “$100,000 or 200 transactions everywhere”;
• tracking only direct-site sales;
• excluding marketplace sales where the state includes them;
• assuming marketplace collection eliminates all seller obligations;
• measuring payment-processor deposits instead of gross transactions;
• excluding wholesale or exempt sales without checking the state’s threshold base;
• registering and then forgetting returns;
• missing required zero returns;
• hard-coding one statewide tax rate;
• overlooking fulfillment inventory;
• registering historical periods before evaluating VDA options;
• assuming tax software also completed state registration;
• checking nexus only once per year.

A useful broader control framework is to treat sales tax like any other recurring : assigned owner, documented rules, recurring review, and evidence retention.

FAQs

Keeping Economic Nexus Compliance Manageable as Your Store Grows

A workable economic nexus ecommerce startup process does not require memorizing 50 state laws. It requires a disciplined system: export destination sales, apply current state definitions, separate direct and marketplace activity, monitor physical nexus, record crossing dates, register on the correct schedule, test checkout, and maintain the resulting filing calendar.

The biggest risk is treating nexus as a one-time setup project. Build the review into quarterly finance operations, retain the evidence behind each decision, and recheck primary state guidance whenever a rule, sales channel, fulfillment arrangement, or geographic sales pattern changes.

This article explains general multistate sales-tax compliance and is not individualized legal or tax advice. Businesses with significant historical exposure, disputed nexus, or multi-year unfiled obligations should consider consulting a state-and-local-tax professional.