Since the Supreme Court decided South Dakota v. Wayfair in 2018, a business with a single office can owe sales tax registration in more than 30 states. Physical presence is no longer the only trigger. Cross a state’s sales threshold and you must register there, even with no people or property in the state.
This guide answers the four questions every seller asks: whether you must register, where, when, and how. It covers 2026 economic nexus thresholds, deadlines, retroactive liability, and the step-by-step permit process.
What Is State Sales Tax Registration?
State sales tax registration is the administrative act of getting a sales tax permit from a state taxing authority so you can legally collect and remit sales tax. The permit goes by many names: seller’s permit, sales and use tax permit, or certificate of authority. Nexus is the obligation to register; registration is the act of complying with it.
Once you register, you become a statutory trustee of the state. Tax you collect is the state’s money held in trust, not your revenue. That is why failing to remit collected tax is treated far more seriously, often as theft or fraud, than failing to register in the first place.
What Is Sales Tax Nexus and When Does It Trigger Registration?
Sales tax nexus is the connection that legally obligates you to register in a state. It takes two forms, physical nexus and economic nexus. You must register once either one exists and you make taxable sales in that state.
What is physical nexus?
Physical nexus comes from a tangible presence in a state. It is created by an office, employees, contractors, trade show attendance, or inventory. Inventory counts even when a third party holds it, including Fulfillment by Amazon (FBA) stock and third-party logistics (3PL) warehouse stock. Remote employees can create it too.
What is economic nexus?
Economic nexus comes from sales volume alone, with no physical presence. It was created nationally by South Dakota v. Wayfair (138 S. Ct. 2080, decided June 21, 2018), a 5-4 decision that overturned the physical-presence rule from Quill Corp. v. North Dakota (1992). The Court upheld South Dakota’s $100,000-or-200-transactions standard, per the Supreme Court opinion. Missouri was the last sales-tax state to adopt economic nexus, effective January 1, 2023, per Missouri S.B. 153.
What Are the Economic Nexus Thresholds by State in 2026?
Most states set economic nexus at $100,000 in sales. California and New York use $500,000, and New York also requires more than 100 transactions, so both prongs must be met. The clear 2024 to 2026 trend is states dropping the 200-transaction prong.
| State | Sales threshold | Transaction count | Measurement period | Source |
|---|---|---|---|---|
| California | $500,000 | No | Preceding or current calendar year | CDTFA |
| New York | $500,000 and >100 sales | Yes, both required | Preceding four sales tax quarters | NY Dept. of Taxation and Finance |
| Florida | $100,000 | No | Previous calendar year | Florida Dept. of Revenue |
| South Dakota | $100,000 | No, repealed 7/1/2023 | Current or previous calendar year | SD Dept. of Revenue |
| Indiana | $100,000 | No, repealed 1/1/2024 | Current or previous calendar year | Indiana General Assembly |
| Wyoming | $100,000 | No, repealed 7/1/2024 | Current or previous calendar year | Wyoming Legislature |
| Missouri | $100,000 | No | Previous or current 12 months | Missouri Senate |
| Alaska (local, ARSSTC) | $100,000 | No, repealed 1/1/2025 | Current or previous calendar year | ARSSTC |
Five NOMAD states have no statewide sales tax and require no sales tax registration: New Hampshire, Oregon, Montana, Alaska, and Delaware. Alaska is a special case. Many Alaska localities impose local sales tax through the Alaska Remote Seller Sales Tax Commission (ARSSTC), which removed its transaction threshold effective January 1, 2025, per the ARSSTC.
South Dakota (2023), Indiana (2024), Wyoming (2024), and Alaska (2025) all removed their transaction counts, and more states are following. One caution: how each state defines “sales” varies between gross, retail, and taxable sales, and measurement periods differ. Verify each state against its Department of Revenue or Commenda’s US nexus exposure guide before you rely on it.
Do I Need to Register for Sales Tax?
You must register in any state where you have physical or economic nexus and make taxable sales. You do not register in states with no statewide sales tax. Work the logic in order: check physical presence first, then measure your sales against each state’s threshold, then confirm your products are taxable there.
Marketplace-only sellers get partial cover. Every sales-tax state has marketplace facilitator laws, so platforms like Amazon and Etsy collect and remit on your behalf. You may still need to register in some states, and you almost certainly must if you also make direct sales.
When Do You Have to Register? Deadlines and Grace Periods
Physical nexus obligates you the moment presence begins. Economic nexus obligates you once you cross the threshold, subject to a short grace window that varies by state. A common rule requires registration by the first day of the month starting at least 30 days after you cross.
South Dakota uses exactly that rule. A remote seller must register by the first day of the month that begins at least 30 days after crossing $100,000, per the South Dakota Department of Revenue. Other states trigger the duty on your next transaction after crossing. Check each state, because missing the window starts the retroactive-liability clock.
What Happens If You Register Late? Retroactive Liability Explained
If you had nexus and never registered, you owe the tax you should have collected out of your own pocket, plus penalties and interest. State penalties commonly range from 5% to 25% of the tax due, and interest accrues monthly. Many states run no statute of limitations on unregistered periods, so the lookback can reach your first day of nexus.
What is a Voluntary Disclosure Agreement (VDA)?
A Voluntary Disclosure Agreement (VDA) is a deal where you proactively disclose past liability in exchange for a capped lookback and reduced penalties. Most state VDA programs limit the lookback to three or four years and waive penalties, and nearly every state offers one. Periodic state amnesty programs offer similar relief on a limited timetable.
How Do You Register for Sales Tax? Step-by-Step
You register online with each state’s revenue department, and most permits are free or low cost. Confirm nexus, gather your details, submit on the state portal, receive the permit, then note your assigned filing frequency.
- Confirm you have physical or economic nexus in the state.
- Gather your registration details from the checklist below.
- Register on the state Department of Revenue portal.
- Receive your permit and account number.
- Note the filing frequency the state assigns you.
Department names vary. California uses the California Department of Tax and Fee Administration (CDTFA), Texas uses the Comptroller of Public Accounts, and New York uses the Department of Taxation and Finance. Most permits are free, though a few states charge a fee, such as Connecticut at roughly $100 per the Connecticut Department of Revenue Services.
Sales tax registration checklist
- Federal Employer Identification Number (EIN)
- Legal entity type and formation date
- North American Industry Classification System (NAICS) code
- Officer, owner, and responsible-party details
- Bank account details for remittance
- Estimated annual taxable sales
- The date nexus began in that state
How Long Does Sales Tax Registration Take?
Registration takes anywhere from instant to three business days in states with fully online systems, and two to four weeks where manual or paper review is required. You generally cannot legally collect tax before your permit issues, so register as soon as you cross a threshold. Streamlined Sales Tax registration can cover its member states within days.
How Do You Register for Sales Tax in Multiple States?
You register state by state through each Department of Revenue, or you use the Streamlined Sales Tax (SST) system to register in its 24 member states with one free application, often processed within days, per the Streamlined Sales Tax Governing Board. Sequence by exposure and register first where your liability is largest.
The operational reality is the hard part. Each state means a separate portal, login, filing calendar, and due date. Tracking all of them by hand is where growing sellers slip and miss filings.
What Happens After You Register? Filing and Remittance
Registration creates an ongoing duty to file returns and remit collected tax on the schedule the state assigns, usually monthly, quarterly, or annually based on your sales volume. You must file zero returns even in periods with no sales. Missing a filing triggers penalties even when you owe no tax.
Filing frequency is set by the state, not chosen by you, and higher volume usually means monthly filing. Due dates vary by state, so a compliance calendar matters once you register in more than a few states.
What Are the Most Common Sales Tax Registration Mistakes?
The most common mistake is registering late, which triggers retroactive liability and penalties. The second is the opposite error, registering too early in states where you lack nexus, which creates filing obligations with no benefit. Both are avoidable with accurate nexus tracking.
- Registering late and triggering retroactive tax, penalties, and interest.
- Registering too early or where you lack nexus, creating needless filing duties.
- Collecting tax before the permit issues, which is not legal.
- Misreading which sales count toward a threshold, such as gross versus taxable.
- Ignoring the assigned filing frequency and missing zero returns.
- Assuming marketplace collection removes every registration duty.
How Commenda Helps With State Sales Tax Registration
Commenda’s indirect tax platform tracks your physical and economic nexus exposure across all 50 states and handles registration and filing in one place. It monitors your sales against each state’s live threshold, alerts you before you cross, and runs the state-by-state registrations so you never miss a deadline or a zero return.
Use the US nexus exposure guide to check current thresholds by state, and the sales tax calculator to look up rates at checkout. Commenda connects to 100+ ERP, API, and custom integrations, so your transaction data flows in automatically.
Book a demo to get a free nexus exposure assessment across all 50 states and see exactly where you need to register.
