An online business can start in one state and acquire customers in all 50 almost overnight. That does not mean it should immediately open 50 sales tax accounts. But it also does not mean an internet business only needs to worry about sales tax in its home state.
The real question is:
When does a business's connection with a state become strong enough that it must register, collect applicable sales tax, file returns, and remit the tax?
That connection is generally called sales tax nexus.
Since the U.S. Supreme Court's South Dakota v. Wayfair decision, physical presence is no longer the only path to nexus. States can require qualifying remote sellers to collect sales tax even without an office, employee, or warehouse in the state.
Streamlined Sales Tax summarizes the modern rule simply: a seller with physical presence generally has registration obligations regardless of remote-seller thresholds, while a remote seller can become required to register after meeting the state's economic nexus threshold.
But that is only the beginning. A proper registration analysis also needs to determine:
Whether physical nexus already exists
Which sales count toward economic nexus
What measurement period the state uses
Whether marketplace sales count
Whether the business sells taxable products or services
When collection must begin after crossing the threshold
Whether another tax registration is triggered
What happens if nexus later disappears
The Short Answer
An online business should review sales tax registration when any of the following occurs:
It establishes physical presence in a state.
It crosses that state's economic nexus threshold.
It stores inventory or other property there.
Employees, representatives, contractors, or other activities create nexus.
It begins making taxable direct sales in a state where it already has nexus.
Marketplace and direct sales together create a state-specific registration requirement.
The business voluntarily elects to register.
The important distinction is Economic nexus is only one reason to register.
What Does “Register for Sales Tax” Actually Mean?
States use different terminology. You may encounter:
Sales Tax Permit
Seller's Permit
Sales and Use Tax Permit
Certificate of Authority
Certificate of Registration
Use Tax Account
Business License with sales tax authority
Despite the different names, the practical purpose is similar.
Registration establishes the seller's tax account with the state and generally gives the business authority or responsibility to collect applicable sales or use tax.
Once registered, the business may also receive:
Filing frequency
Account number
Effective date
Online filing credentials
Local-tax obligations
Resale documentation
Specific reporting instructions
Registration is therefore not merely obtaining a number. It creates an ongoing compliance relationship.
Nexus Comes Before Registration
Before opening an account, determine why the business may need one. The two major nexus categories are:
Physical Nexus
The business has sufficient physical activity or presence in the state.
Economic Nexus
The business has enough economic activity in the state to create a collection obligation even without physical presence.
A business can have either one. Or both.
Physical Nexus Can Trigger Registration Before You Reach $100,000
One of the biggest mistakes online sellers make is believing:
“We have less than $100,000 of sales in the state, so we don't have nexus.”
That may be completely wrong. Economic nexus thresholds are primarily relevant when the seller does not already have physical presence.
Physical presence can arise through activities such as:
Office
Store
Employee
Warehouse
Inventory
Equipment
Property
Sales representatives
Installers
Certain contractors or agents
Temporary business locations
Other in-state activities
California, for example, identifies offices, warehouses, storage places, representatives, agents, contractors performing certain activities, equipment, servers, and other property as potential physical-presence connections requiring collection.
Streamlined Sales Tax similarly warns that a seller with physical presence generally is not treated as a remote seller for threshold purposes and should review registration regardless of sales volume.
Employees Working Remotely Can Matter
Suppose your company is headquartered in Florida.
One employee moves permanently to another state and continues working remotely. The company may now have an employee performing business activities inside that state. That can create more than a sales tax issue.
Potential consequences can include:
Sales tax nexus
Income or franchise tax nexus
Payroll withholding
Unemployment registration
Workers' Compensation
State business registration
The exact consequences depend on the state and employee's activities, but a remote-work move should never be treated solely as an HR address update.
Inventory and Fulfillment Centers
Ecommerce businesses need to pay particular attention to where inventory is physically stored.
If merchandise is stored in a state, that can create physical nexus even when the business:
Has no office there
Has no employee there
Never personally visits the state
This can affect businesses using:
Third-party warehouses
Fulfillment providers
Distributed logistics networks
Marketplace fulfillment programs
California specifically recognizes inventory, warehouses, storage locations and other property as potential physical-presence connections. Marketplace facilitator collection does not automatically make the inventory disappear for nexus purposes.
What Is Economic Nexus?
Economic nexus allows a state to impose collection obligations on qualifying remote sellers based on their economic activity rather than physical presence.
The basic structure looks like:
Remote seller + sufficient in-state sales/activity = registration obligation
But every state does not use the same threshold.
Common structures include:
$100,000 of sales
$500,000 of sales
Sales plus transaction counts
Gross receipts
Retail sales
Taxable sales
Current calendar year
Previous calendar year
Rolling 12 months
Previous four sales tax quarters
Our Economic Nexus Thresholds by State: 2026 Sales Tax Guide for Online Sellers provides the state-by-state thresholds. This article focuses on what happens after those numbers start becoming relevant.
Not Every State Uses $100,000
It is dangerous to build a nationwide rule around “Register once sales exceed $100,000.” Examples show why.
Florida
Florida generally requires a qualifying out-of-state retailer with no physical presence to register when it had more than $100,000 of taxable remote Florida sales in the previous calendar year.
Texas
Texas provides a remote-seller safe harbor when total Texas revenue is less than $500,000 during the preceding 12 calendar months.
California
California generally uses a $500,000 threshold based on total combined sales of tangible personal property for delivery into the state during the current or prior calendar year.
New York
New York currently uses both:
More than $500,000 in qualifying gross receipts;
and
More than 100 qualifying sales
during the immediately preceding four sales tax quarters. Both tests must be satisfied.
Washington
Washington generally requires a remote seller to register when it has more than $100,000 of combined gross receipts sourced or attributed to Washington in the current or prior year.
Five states. Four very different systems.
The Threshold Is Not Always Based on Taxable Sales
This is another frequent mistake.
A business may think:
“We only had $40,000 of taxable sales, so we're nowhere near nexus.”
But the state may count:
Exempt sales
Wholesale sales
Marketplace sales
Nontaxable services
Other gross receipts
depending on its statute.
Texas calculates its $500,000 safe harbor using gross revenue from taxable and nontaxable sales and expressly includes sales for resale and sales to exempt entities.
Washington's $100,000 threshold includes exempt sales and sales made through marketplace facilitators.
California's $500,000 test can include nontaxable sales such as sales for resale.
Therefore Tax collected is a terrible proxy for economic nexus exposure.
Product Taxability and Nexus Are Different Questions
Every online seller should separately answer:
Question 1
Do we have nexus?
Question 2
Is what we sell taxable?
These are not the same question.
A company can Have nexus + sell exempt products or Sell taxable products + not yet have nexus or Have nexus + sell a mixture of taxable and exempt products.
This distinction is particularly important for:
SaaS
Digital products
Professional services
Food
Medical products
Manufacturing transactions
Wholesale sales
Our Sales Tax on Digital Products & SaaS by State: 2026 Guide demonstrates how dramatically product taxability can differ from one state to another.
Does Selling Only Exempt Products Mean You Never Register?
No universal answer exists.
Some states' nexus thresholds can be reached with exempt or nontaxable sales. Whether registration is then required can depend on the state's rules.
California illustrates the nuance well. Sales for resale count toward California's $500,000 economic nexus threshold.
But an out-of-state wholesaler making only qualifying sales for resale and no California retail sales generally does not need to register merely to collect use tax. If it crosses the threshold and begins making retail sales, registration can become necessary.
The correct analysis therefore goes beyond Threshold crossed = register immediately everywhere.
When Do You Actually Start Collecting After Crossing the Threshold?
States use different transition rules. This is one of the most important operational parts of sales tax compliance.
State | General Remote-Seller Threshold | General Collection Timing |
|---|---|---|
Florida | More than $100,000 taxable remote sales in previous calendar year | Registration/collection obligation based on prior-year threshold |
Texas | $500,000 total Texas revenue safe harbor | Begin no later than first day of fourth month after month threshold is exceeded |
California | More than $500,000 current or prior calendar-year TPP sales | Registration required when threshold is reached; CDTFA example begins collection on subsequent sales after crossing |
New York | >$500,000 and >100 sales during preceding four sales tax quarters | Evaluate after each sales tax quarter and register when prior four quarters satisfy both tests |
Washington | More than $100,000 combined gross receipts current/prior year | First day of month beginning at least 30 days after threshold is met |
This table alone demonstrates why sales tax software should not use:
Threshold reached → collect tomorrow
as a universal rule.
Registration Is Not Retroactive in the Same Way Everywhere
If you discover nexus late, do not immediately register using an arbitrary current date.
First determine:
When nexus actually began
When the state required collection to begin
Whether prior returns are due
Whether tax should have been collected
Whether customers can still be billed
Whether use tax was potentially paid by customers
Whether penalties and interest apply
Whether a voluntary disclosure program should be considered
For significant historical exposure, blindly registering before analyzing prior periods can complicate the cleanup.
Marketplace Facilitators Changed Collection — Not Nexus Analysis
Amazon, Etsy, eBay, Walmart, and other qualifying marketplace facilitators generally collect and remit sales tax on facilitated transactions under state marketplace laws.
That does not mean every marketplace seller can forget about state registration.
A marketplace seller can still have:
Physical nexus
Inventory nexus
Employees
Direct website sales
Wholesale transactions
B&O or gross receipts taxes
Income/franchise tax obligations
State-specific marketplace registration requirements
Our Marketplace Facilitator Sales Tax: Amazon, Etsy, eBay & Walmart Explained (2026) covers the marketplace rules in detail.
Florida Marketplace Seller Example
Florida provides a relatively straightforward example.
When the marketplace provider certifies that it will collect and remit Florida tax, the marketplace seller does not collect the tax on those facilitated Florida transactions.
A marketplace seller with physical presence in Florida, however, still has registration considerations.
And a remote marketplace seller making more than $100,000 of qualifying Florida sales outside the marketplace can have its own dealer-registration and collection obligation.
Therefore: Amazon sales and website sales should not automatically be combined operationally as though the same party collects the tax.
Washington Marketplace Seller Example
Washington illustrates why the answer can be even more complicated.
A remote marketplace seller can have a registration obligation after exceeding Washington's $100,000 combined gross-receipts threshold. Washington includes sales through marketplace facilitators when calculating that threshold.
If all retail sales are made through a facilitator, the seller generally does not itself collect and remit retail sales tax on those facilitated sales when it has proof the facilitator is doing so. But registration can still matter because Washington also imposes Business & Occupation tax. Sales-tax collection responsibility and state-registration responsibility are therefore not always identical.
California Marketplace Sales Can Count Toward the Threshold
California also includes qualifying marketplace sales when determining the $500,000 economic nexus threshold.
However, when all of a remote seller's California sales are facilitated by registered marketplace facilitators and other registration triggers are absent, California provides marketplace-specific relief from having the seller collect tax on those facilitated transactions.
Again: Marketplace collects ≠ marketplace sales disappear from every nexus calculation.
New York Marketplace Sales Also Count
New York expressly instructs remote sellers to include marketplace sales when determining whether the seller exceeds its $500,000-and-100-sales economic nexus test. That makes accurate marketplace data essential even if the marketplace remits every dollar of sales tax itself.
Should You Register Before You Cross the Threshold?
Sometimes businesses voluntarily register before a legal requirement arises.
Reasons might include:
Expected rapid growth
Upcoming product launch
Customer requirement
Resale documentation
Simplifying future operations
Participation in a multistate program
But voluntary registration should not be treated casually.
Once registered, you may be required to:
Collect applicable tax
File periodic returns
File zero returns
Remit collected tax
Maintain exemption certificates
Respond to notices
Continue filing until the account is formally closed
New York specifically warns that a business choosing to remain registered must continue filing sales and use tax returns for each reporting period even when it has no qualifying sales requiring collection.
Do Not Register in 45 States Just Because Software Makes It Easy
Modern tax engines can make registration feel almost effortless. The compliance afterward is not effortless.
Forty registrations can mean:
Monthly returns
Quarterly returns
Annual returns
Local returns
Zero returns
Notices
Reconciliations
Certificate management
State account maintenance
Closing procedures
Filing fees and professional costs
Registration should follow a tax analysis. Not a software checkbox.
Streamlined Sales Tax Can Simplify Registration
For businesses that actually need registrations across multiple Streamlined states, the Streamlined Sales Tax Registration System (SSTRS) can simplify the process. Sellers can use one registration system to register in selected Streamlined member states. As of August 31, 2026, Streamlined reports more than 35,000 active registrations through the system.
However, registering through SSTRS still creates tax responsibilities beginning with the applicable registration date.
It is a registration tool. Not a way to avoid determining where the company actually has obligations.
What Information Is Usually Needed to Register?
States commonly ask for information such as:
Legal entity name
DBA
EIN
Entity type
Business address
Owners/officers
NAICS or business activity
Products/services sold
Nexus start date
First taxable sale date
Estimated sales
Existing state accounts
Marketplace activity
Locations
Contact information
Registration answers should be consistent with the company's actual operations. Guessing the nexus start date can create future problems.
Registration Date vs. First Collection Date
These dates are related but should not be confused.
You may have:
Nexus date
↓
Required registration date
↓
Collection start date
↓
First return period
They may not all be identical. Accounting should document each one.
What Happens After Registration?
Registration is the beginning, not the end. The business must generally establish a workflow for:
Tax Calculation
Determine the correct rate based on sourcing rules.
Product Taxability
Tax the right products and services.
Exemption Management
Collect and verify resale and exemption certificates.
Filing
File according to the frequency assigned by the state.
Remittance
Pay tax on time.
Reconciliation
Tie: tax engine → invoices → General Ledger → sales tax return → payment
Account Maintenance
Update addresses, entity changes, locations, ownership changes, or closure when required.
Filing Frequency May Change
A business may begin as a quarterly filer and later become monthly as its sales or tax liability increases. Or the opposite. Never assume the filing cadence shown when the account was opened will remain permanent. State notices matter.
Zero Returns Still Matter
Once registered, many states expect returns even when:
No taxable sales occurred
Marketplace collected all tax
Sales temporarily stopped
Revenue fell below the threshold
Business became seasonal
Ignoring a zero return can generate automated notices and estimated liabilities. Closing or canceling a registration is a separate process.
What If Sales Later Fall Below the Threshold?
Do not simply turn off tax collection. States use different rules.
Washington
After exceeding its threshold, Washington generally requires the remote seller to remain in the system for the rest of the current calendar year and the following calendar year.
New York
A remote business whose immediately preceding four quarters no longer exceed both New York tests and that has no other nexus can potentially file a final return and surrender the Certificate of Authority.
Texas
Texas provides a process allowing qualifying remote sellers with no physical presence to terminate remote-seller use-tax responsibilities after having 12 consecutive calendar months below its $500,000 safe harbor.
Three states. Three different exit rules.
Five States Without a General Statewide Sales Tax
The familiar five are:
Alaska
Delaware
Montana
New Hampshire
Oregon
But do not automatically translate that into “No registration issue.”
Alaska has local sales taxes. Businesses can also have other state and local taxes unrelated to general retail sales tax. A comprehensive multistate analysis should never stop at State sales tax rate = 0%.
Collecting Tax and Registering Are Not the Same as Paying Income Tax
Another source of confusion:
Sales tax nexus does not necessarily determine:
Corporate income tax
Franchise tax
Gross receipts tax
Payroll tax
Business licensing
Secretary of State registration
Texas is a perfect example. Its sales/use tax remote-seller rules and Texas Franchise Tax nexus rules are separate frameworks.
Washington similarly combines retail sales tax issues with its separate B&O tax regime. One tax registration analysis cannot automatically answer every state tax question.
Common Sales Tax Registration Mistakes
Assuming an online business only registers in its home state.
Registering in every state immediately after launching.
Looking only at the $100,000 economic nexus number.
Ignoring physical nexus because sales are below the economic threshold.
Ignoring remote employees.
Ignoring inventory stored by third-party fulfillment providers.
Counting only taxable sales toward economic nexus.
Ignoring marketplace sales when the state includes them in its threshold.
Assuming marketplace collection eliminates every state registration obligation.
Waiting until year-end to monitor nexus when the state uses a current-year or rolling threshold.
Starting collection before determining the proper registration process.
Using the registration date as the nexus date without analysis.
Registering voluntarily without understanding filing obligations.
Stopping returns simply because sales declined.
Ignoring zero returns.
Failing to formally close inactive accounts.
Sales Tax Registration Decision Tree
Question 1 — Do You Have Physical Presence?
Office, employee, inventory, warehouse, property, representative, or other qualifying activity?
Yes → Review registration now.
No → Continue.
Question 2 — What Are Your Sales Into the State?
Determine:
Gross sales
Retail sales
Taxable sales
Exempt sales
Marketplace sales
Transaction count
according to that state's threshold rules.
Question 3 — Have You Crossed Economic Nexus?
Yes → Determine the state's required registration and collection start date.
No → Continue monitoring.
Question 4 — Are Sales Made Through a Marketplace?
Determine:
Which sales are facilitated
Who collects tax
Whether marketplace sales count toward nexus
Whether direct sales exist
Whether another state tax still requires registration
Question 5 — Is the Product Taxable?
Determine which transactions actually require collection after registration.
Question 6 — Are Exemptions Involved?
Collect the correct resale or exemption documentation.
Question 7 — When Must Collection Begin?
Do not assume the deadline. Document the state-specific start date.
A Practical Monthly Nexus Review
A growing online business should not wait for tax season to look at nexus. At least monthly, review each state for:
Current-year gross sales
Prior-year sales
Rolling 12-month sales when relevant
Transaction counts where relevant
Direct website sales
Marketplace sales
Taxable sales
Exempt sales
New employees
Employee relocations
Inventory locations
New warehouses
Contractors or representatives
New products
Product taxability changes
States approaching thresholds
Registration deadlines
Collection start dates
Active permits
Filing status
A state approaching 90% of its threshold deserves far more attention than one with $800 of annual sales.
Sales Tax Registration Checklist
Before registering in a new state, determine:
What creates nexus?
Is it physical or economic?
When did nexus begin?
What measurement period applies?
Which sales count?
Do marketplace sales count?
Are transaction counts relevant?
Are related entities included?
Are our products taxable?
Do B2B exemptions apply?
Do we make wholesale sales?
Are resale certificates required?
When must registration occur?
When must collection begin?
Which local taxes apply?
What registration form is required?
Can SSTRS be used?
What filing frequency will apply?
Are zero returns required?
Who owns the compliance process internally?
Is the tax engine configured?
Is accounting mapped correctly?
Are exemption certificates stored?
Is marketplace activity segregated?
Has historical exposure been reviewed?
Should voluntary disclosure be considered?
What happens if sales later fall below threshold?
How is the account eventually closed?
Are other state taxes triggered?
Can every registration decision be supported during an audit?
Final Takeaway
An online business should not ask only:
“Did we hit $100,000?”
The better questions are:
Do we already have physical nexus?
Which sales count toward the state's economic threshold?
What time period does the state measure?
Do marketplace sales count?
When did we actually cross the threshold?
When does collection have to begin?
Is our product taxable?
Do we need registration even if someone else collects the sales tax?
What filing obligations begin once we register?
Sales tax registration is not simply a form. It is the moment a business enters an ongoing compliance relationship with a state.
The goal is therefore not to register as many places as possible or as late as possible.
It is to register in the correct jurisdictions, at the correct time, with the correct effective date, and with a system ready to collect, report, reconcile, and remit the tax correctly.
Need Help Determining Where Your Business Should Register?
Multistate sales tax becomes increasingly complex as an online business adds customers, marketplaces, employees, warehouses, digital products, and direct sales across state lines.
At Capital Edge Firm, we help businesses evaluate physical and economic nexus, registration requirements, product taxability, exemption documentation, marketplace transactions, use tax, and multistate sales tax filings.
If your business sells online and you're uncertain which states actually require registration—or when collection should begin—contact Capital Edge Firm to review your sales tax footprint before opening unnecessary accounts or allowing an existing obligation to grow.
Disclaimer: This article is provided for general educational purposes only and does not constitute legal or tax advice. Nexus standards, economic thresholds, marketplace rules, registration deadlines, product taxability, filing requirements, and state guidance can change. Confirm current requirements with the applicable state taxing authority or a qualified tax professional before making material registration or compliance decisions.