U.S. ecommerce sales tax is a state and local tax. You collect it only where you have a duty to collect and only on sales that state treats as taxable. A Shopify setting, a marketplace payout, and a nexus threshold are three different facts.
This guide is the general one. Platform clicks for Shopify are in the Shopify sales tax guide. How a duty is created is summarised here and developed in what sales tax nexus is. Permits, including for companies outside the United States, are in the registration guide. Digital-product rules are not repeated from the SaaS sales tax guide.
If you want that work done for agreed states, Taxolio's ecommerce service is the commercial page. A nexus check lists candidate states. Neither one is a determination for every product you sell.
Not every state imposes a statewide sales tax. Selling into a state that does not is not, by itself, a collection duty. The examples below are labelled with the state they come from. Do not apply one state's threshold, lookback, or marketplace rule to the other forty-nine.
Nexus, taxability, and registration are separate
A sale is your sales-tax problem only when both of these are true:
- You have nexus in the state, from physical presence or from that state's economic-nexus rule.
- The product is taxable there, on the facts of that sale.
Registration is the third step. Once you have nexus, determine whether the state requires registration for your sales profile, and register before collecting any tax. Collecting before the state has authorised you is its own problem. The deadline for registering after you cross a threshold is not the same in every state. Three real deadlines are in the examples below.
Physical presence, including inventory
Physical presence does not depend on crossing a sales threshold.
California's Department of Tax and Fee Administration lists, as physical presence, inventory or an office in California, representatives in the state who take orders, make sales or deliveries, or install or assemble goods, and leased equipment including a computer server. A foreign company is in the same remote-seller rule as a U.S. company based in another state. The page is the CDTFA Wayfair guide.
Inventory in a third-party warehouse is the fact pattern ecommerce sellers miss, because the building is not theirs. California's list includes inventory in the state without requiring that the seller own the building. Other states write their own physical-presence rules. Confirm the state before you treat every fulfilment centre as identical, and before you assume a drop-shipper or an affiliate creates presence everywhere.
An employee working in a state is a common physical-presence fact. It is not a substitute for reading that state's rule on contractors or representatives.
Economic nexus: the test is the state's, not a national default
After South Dakota v. Wayfair (2018), states were allowed to require collection from sellers without a physical presence. New York's Department of Taxation and Finance describes that effect on its nexus page. States did not adopt one threshold.
These statements are too broad to use:
- "Most states use $100,000 or 200 transactions." Some states use a dollar test only. New York requires both a dollar test and a transaction count. Florida's current statute uses a dollar test and does not state a transaction count.
- "Most states use a rolling 12-month period." California and Colorado use calendar years. Texas uses the preceding twelve calendar months. New York uses the preceding four sales-tax quarters.
- "You must collect on the very next transaction in every state." Colorado and Texas both publish a later start date. New York tells a business that has met the test to register immediately.
What the threshold counts, and the lookback
California. More than $500,000 of tangible personal property delivered into California, including related persons as California defines them. No transaction count on this test. Lookback: the preceding or current calendar year. Source: CDTFA Wayfair guide.
Texas. $500,000 or more of total Texas revenue. That is gross revenue from taxable and nontaxable sales of tangible personal property and services, including handling and similar fees you collect, sales for resale, and sales to exempt entities. No transaction count. Lookback: the preceding twelve calendar months. Source: Comptroller remote sellers.
New York. Both more than $500,000 of gross receipts from tangible personal property delivered into New York and more than 100 such sales. Lookback: the immediately preceding four sales-tax quarters (Mar鈥揗ay, Jun鈥揂ug, Sep鈥揘ov, Dec鈥揊eb). Source: NY DTF nexus guidance.
Florida. Taxable remote sales whose sales prices exceed $100,000. The statute's definition does not add a transaction count. Lookback: the previous calendar year. Source: Fla. Stat. 搂 212.0596 (2025).
Colorado. $100,000 of retail sales into Colorado. At or above that figure, the licensing rule below applies. Under it in both the current and previous calendar years, a retailer with no Colorado location is outside state licensing, with separate notice duties. Source: Colorado DOR: out-of-state businesses.
California's test is tangible personal property, so it is not a test of every dollar of revenue. Texas's test expressly includes services and exempt sales. Using either state's rule in the other state is a mistake. More state detail for California is in the California nexus guide. This page does not repeat a 50-state table.
Direct sales and marketplace sales
On a marketplace order, the marketplace is often the party required to collect and remit. On a sale through your own site, that duty stays with you once you are the seller with nexus.
Whether the marketplace sale also counts toward your economic-nexus threshold is a different question, and the states above do not agree:
- New York. The Department says sales you make through an online marketplace should be included when you test the $500,000 and 100-sale thresholds.
- California. The threshold includes sales of tangible merchandise facilitated through a marketplace, as well as your own sales and those of related persons. See the Marketplace Facilitator Act guide. The facilitator is generally the retailer for the facilitated sale itself from 1 October 2019, which means the facilitator collects on that sale. Your direct sales remain yours.
- Texas. A remote seller that sells only through a marketplace provider which certifies that it collects and reports Texas tax does not have to hold a Texas permit. Records of marketplace sales still have to be kept for at least four years. The Comptroller's safe-harbor description of "total Texas revenue" does not, on that page, say to exclude marketplace sales when you also have direct Texas sales. Do not invent an exclusion the page does not state.
Florida's remote-sales statute, as read for this guide, does not answer the marketplace-counting question in the definition of a remote sale. Do not fill that gap from another state's rule.
Three hypothetical examples
These are illustrations. They are not Taxolio clients. Each one states its assumptions. Change an assumption and the result can change.
California: under the dollar test
Assumptions: no inventory, office, employees, or other physical presence in California; no related persons with California sales; the figure is tangible personal property delivered in California during the current calendar year; no sales in the preceding calendar year.
Direct-store sales: $420,000.
$420,000 is not more than $500,000. This figure alone does not meet California's economic-nexus test. Physical presence, if it existed, would be a separate registration reason. Recheck when either calendar year can exceed $500,000.
Colorado: not the next invoice
Assumptions: no physical location in Colorado; the figures are the retail sales into Colorado that the Department uses for this rule; previous calendar year sales were $70,000; the current calendar year first exceeds $100,000 on 15 March 2026.
Colorado says a retailer in that position must obtain a licence and begin collecting by the first day of the first month that commences at least 90 days after the day the current-year sales exceed $100,000.
15 March 2026 plus 90 days is 13 June 2026. 1 June is only 78 days later, so it is too soon. The first month-start that is at least 90 days later is 1 July 2026.
If instead the previous calendar year had already exceeded $100,000, Colorado says the retailer is subject to licensing and collection for the entire current calendar year. There is no 90-day wait in that case. The same dollar figure produces two different start dates depending on which year crossed the line.
New York: both tests, marketplace included
Assumptions: no physical presence in New York; the figures are tangible personal property delivered into New York during the immediately preceding four sales-tax quarters.
- Direct store: $480,000 and 80 sales.
- Marketplace orders: $40,000 and 30 sales.
New York says to include the marketplace sales. Combined gross receipts are $520,000. Combined sales are 110. Both are over the line (more than $500,000 and more than 100). The business must register and collect.
The marketplace may still be the party that collects on the marketplace orders. The direct-store orders are the seller's collection duty once registered. Meeting the threshold is not the same statement as "charge tax on the Amazon order yourself."
Interstate delivery and in-state origin rules
For an order shipped to a customer in another state, that destination state's rules decide whether the sale is taxable and which rate applies, once you have a duty to collect there.
Texas states this for remote sellers: local use tax is due at the Texas location where the order is shipped or delivered, when the order is not received or fulfilled from a Texas place of business. A remote seller may instead elect Texas's single local use tax rate of 1.75 percent. A business located in Texas is not a remote seller and cannot use that single rate. Source: the Comptroller remote-seller page.
Some states source local tax on a sale that starts and ends inside the state to the seller's location. That is an intrastate rule. It does not mean an online seller charges one home-state rate on every order, regardless of where the customer is.
Product exemptions and shipping
Tangible goods are the usual ecommerce case, and they are not uniformly taxable. Clothing, grocery food, and medical products are taxable, partly exempt, or fully exempt depending on the state and sometimes on the item price. A category that is right for your home state is not evidence about the destination state.
Shipping and handling are the same kind of question. Some states tax a delivery charge that is part of the sale of a taxable good, and some do not, especially when the charge is stated a certain way. Shopify can apply a shipping override, but that override is a checkout control. The state's rule is the reason you would set it. The Shopify guide covers the override warning: a U.S. override is statewide and drops local tax.
Exemption certificates are buyer-specific. A resale or entity-based exemption generally requires a certificate the state accepts, kept for the period that state can still ask. Accepting the customer's word in a checkout note, with nothing on file, leaves the tax with the seller if the state audits the sale. New York and other states publish their own forms. There is no single national certificate.
Sales-tax holidays are short, statutory windows. They apply only to the items and dates that state lists. They are not a reason to turn tax off for a product category all year.
Registration and when collection starts
Register before you collect. The start date still follows the state:
- Colorado, if only the current year has crossed $100,000: the first day of the first month commencing at least 90 days later, as in the example above. If the previous year had already crossed, the entire current year.
- Texas: a remote seller that crosses $500,000 must get a permit and begin collecting no later than the first day of the fourth month after the month the threshold is exceeded. The Comptroller's example: Texas revenue over the safe harbor during 1 July 2021 through 30 June 2022 means a permit by 1 October 2022.
- New York: a business that meets both tests must register immediately if it has not already done so, and begin collecting.
Processing time is whatever that state's office is taking. It is not a national "ten business days."
Non-U.S. companies are inside these rules when they have the presence or the sales. California's guide says so expressly for retailers outside the United States. Form details that are specific to foreign sellers, such as an EIN, are in the registration guide. Selling into the United States does not mean every state requires a permit on the first order.
Filing, reconciliation, and records
After registration, the state assigns a filing frequency. High sales in one state and low sales in another often produce different frequencies. Due dates differ. "The 20th" is common and not universal. Do not build a calendar from one state's portal.
A registered account can still have a return due when taxable sales in the period are zero. Whether that zero return is required is a state rule. New York, for example, says a business that stays registered must keep filing. Do not skip a return because the period felt quiet, and do not file one in a state that does not require it, without checking.
Reconcile before you file:
- Sales on your own site, by destination state, for the filing period.
- Sales each marketplace reports, and whether it says it collected the tax.
- Refunds and cancelled orders, in the period the state tells you to use.
- Exempt sales you can support with a certificate.
The amount collected at checkout can differ from the amount the return computes, because of exemptions, refunds, a local rate, or a state rule that taxes something the checkout did not. Find that difference before the return is submitted.
Keep the return, the confirmation, the sales reports, and the certificates for as long as that state can still examine the period. Texas's remote-seller page requires marketplace-sales records for at least four years. That sentence is Texas-specific. It is not a national retention period.
What this guide is not
It is not a Shopify click-path. Use the Shopify guide for calculation, reports, and automated filing.
It is not a VAT or GST guide. A non-U.S. seller can have U.S. sales tax from inventory or from a state's economic test and, separately, a consumption tax in the country of the customer. Those are different systems. This page does not state foreign registration thresholds.
It is not a statement that every online seller is already exposed. A seller under a state's threshold, with no physical presence there, and with no marketplace-counting surprise of the kind New York and California describe, may have nothing to register yet. The work is to test the states where the sales and the inventory actually are.
Taxolio does that review from reports you provide, then registrations and filings for the states in scope. The nexus checker is the unscoped first pass.