Sales Tax Tracking Basics for Online and Multi-State Sellers

A sale that is fine in your home state can create a bill in the state where the box lands. The IRS will not answer which bill.

The IRS says the question “Does my business need to collect sales tax?” is a state tax question. The state revenue department has the answer. Sales tax tracking is how you know which department to call before the totals surprise you.

What sales tax is

Small business sales tax is money you may have to add to a customer’s price and send to a state or a local government. The SBA says not every state and not every locality has a sales tax. Most states exempt some items. Food and clothing are the SBA’s examples. If you charge the tax, you need the rate that applies to that sale.

The IRS does not run that system. Its small-business FAQ tells you to use state government websites. Keep that split in mind when a federal estimated-tax payment and a state sales-tax return fall in the same month. They are not the same filing.

Sales tax nexus basics are the reason an online sale can create a duty outside your home state. The SBA says you may have to collect state and local sales tax from customers in a state where you have a physical or economic presence. The examples on that page are a physical location or employees or a certain amount of income. The SBA calls that presence nexus. It says most states use different standards.

SCORE’s 2026 materials describe the same split in time. Before 2018, the nexus that mattered for online sales was physical. A storefront or an office or a warehouse can be that presence. So can an employee or a contractor who solicits sales. If you have that presence in a state, SCORE says you collect the sales tax that applies from online customers in that state.

In June 2018 the Supreme Court decided South Dakota v. Wayfair. SCORE says that decision allows economic nexus. A business can cross the line with enough sales into the state even when it has no building and no person there. The Texas Comptroller describes the same case. States can require collection from a seller with an economic presence and no physical presence. The thresholds are not one national number. SCORE says they vary by state and can be a count of sales or a dollar total or both.

Why the tracking has to be by state

Track sales tax by state because the tests do not match. These figures are the rules on each state’s own page. They are not a shortcut for a state that is absent from the list.

SCORE’s 2026 deck adds two more dated examples. Missouri’s economic-nexus line is one hundred thousand dollars of sales effective January 1 of 2023. Kansas uses one hundred thousand dollars of sales effective July 1 of 2021. Treat those as SCORE’s examples. Confirm them on the state site before you rely on them.

A 2019 SCORE article discusses Quill and prints a list of dollar limits. That list does not match the state pages above. Washington’s page uses one hundred thousand dollars. The 2019 article prints a higher Washington figure. Use the state revenue department for the number. Use SCORE for the idea that the number moves.

Multi-state sales tax depends on what you count. Texas counts gross revenue from taxable and nontaxable sales of tangible personal property and services into Texas. Separately stated handling and transportation and installation and similar fees go into that total. Sales for resale go in. Sales to exempt entities go in. You can be under a “taxable sales” guess and over the Texas line.

Minnesota counts retail sales shipped into the state. One sale of ten items to one customer is one retail sale. Leave out a sale for resale when the buyer gives you a completed Form ST3 exemption certificate. Add every channel. Your site and a marketplace and any other source go into one Minnesota total.

Washington’s one-hundred-thousand-dollar line is combined gross receipts. The page says that includes retailing and wholesaling and services and other activities. Retail sales in the count include direct sales and exempt sales and marketplace sales.

If you track only “taxable product sales on my own site,” you can miss the line each of these states describes.

When collection starts

Crossing the line and charging the tax are not the same day on these pages.

The Texas Comptroller says a remote seller who passes five hundred thousand dollars gets a permit and starts collecting on the first day of the fourth month after the month the total is crossed. The page’s example runs from July 1 of 2021 through June 30 of 2022. If that period is over the line, the permit date in the example is October 1 of 2022. You keep records of sales into Texas.

Minnesota says you register and collect and remit starting the first day of a calendar month. That start date falls within sixty days after you pass the small-seller exception. You then keep collecting at least through the last day of the twelfth calendar month after the month you started. You may stop only after you notify the department that you stopped soliciting Minnesota customers and you verify that you stayed under the lines for the twelve months after collection began.

Washington says a seller who missed the dollar line last year starts collecting on the first day of the month that begins at least thirty days after the day the line is met. A seller with physical presence registers and collects from the date that presence begins. The dollar line does not delay that date.

E-commerce sales tax gets messy when you learn about the line after the start date has passed. The records that show the day you crossed it are the records that show whether the tax should have been on the invoice.

Marketplaces and your own checkout

Collect sales tax online on your own checkout only for the sales the marketplace does not collect for you. Read that state’s page before you assume the split.

Minnesota says you do not collect on taxable sales when a marketplace provider collects and remits for you. You do collect on taxable sales from your site and from other sources that do not collect for you, once your combined retail sales meet the exception.

Texas says a remote seller who sells only through a marketplace provider does not need a Texas permit if that provider certifies it is collecting and reporting the tax. Every seller keeps required records of marketplace sales for at least four years.

Washington includes marketplace sales in the gross-receipts line. A remote marketplace seller who is over one hundred thousand dollars registers to report business and occupation tax and collects sales tax under that page’s timing rule.

SCORE’s 2026 deck says a third-party platform can be required to collect and remit. That does not erase your copy of the sale. The state pages above want the marketplace dollars in the file even when the platform sends the tax.

The rate is a second map

Sales tax compliance fails when the state is right and the local rate is wrong. The SBA says charging the tax means knowing the rates that apply. Many retailers use shopping-cart software to calculate them. The SBA says to account for the different state rates in the sales plan and to call the state’s Department of Revenue or a local district office.

Washington says the tax applies to the selling price and must be stated separately on the receipt or invoice. The selling price includes shipping and delivery. The rate follows the place where the sale is sourced or delivered. The department’s tools look up the rate and the location code. You owe the correct tax even if you collected the wrong amount from the customer.

Texas has a different local option for remote sellers. Local use tax is due where the order is shipped or delivered when the order is not received or filled from a Texas place of business. The Comptroller offers a rate locator by address. A remote seller may instead collect a single local use tax rate. The page says the current rate is 1.75 percent and that the rate is published in the Texas Register by January 1 each year. A business located in Texas cannot use that single rate. A marketplace provider collecting for sellers cannot use it either.

The single rate is simpler. Leaving it is slow. The Comptroller’s examples keep a seller on that rate until a January 1 after the revocation notice. The form is 01-799. Read the timing on that form before you switch a year of invoices back to destination rates.

Michigan’s treasury department points multi-state remote sellers to Streamlined Sales Tax for member states. One application there can open accounts in member states. If a state is not a member, Michigan says to contact that state. Streamlined does not set Texas or Minnesota or Washington for you. It is a registration path for the states that joined.

Two other state duties that are not the sales-tax return

The SBA treats expansion as its own checklist. A new state or county or city can mean a new license or permit. Zoning rules differ. A federal license you hold may or may not cover the new state. Ask the agency that issued it.

Foreign qualification is the notice that your company is active in the new state. The SBA says you file a Certificate of Authority. Many states want a Certificate of Good Standing from the state where you formed. Fees vary. A foreign-qualified business pays taxes and annual report fees in the new state and in the home state. That page describes the tax step as similar to any other business that pays tax in the state. It is not a substitute for the sales-tax permit.

Texas shows how the two can share a dollar figure and stay different taxes. The Comptroller says the franchise tax is a privilege tax on a taxable entity formed or organized or doing business in Texas. A foreign entity with annual Texas gross receipts of five hundred thousand dollars or more has franchise-tax economic nexus even with no physical presence. That is a franchise-tax report. It is not the use-tax permit. Track the receipts once. Ask which return each total feeds.

What to record on each order

Build the file from the tests above. A national “taxable sales” column will not answer them.

1. Date of the sale.
2. Ship-to state. Add the delivery address when you may need a local rate. Texas looks up rates by address. Washington looks up a location code from where the sale is sourced or delivered.
3. Channel. Your site or a marketplace or another source. Minnesota adds them. Washington includes marketplace sales in the dollar line. Texas asks whether the marketplace certified collection.
4. What the state counts. In Texas, put taxable sales and nontaxable sales and resale sales and exempt sales and the handling and shipping and installation fees in the revenue total. In Minnesota, count retail transactions and drop resale sales only when you have Form ST3.
5. Tax you charged, stated on its own line. Washington requires that separate statement and includes shipping in the selling price.
6. A running total of dollars and of transactions for the period that state measures. Texas uses the preceding twelve calendar months. Minnesota uses the prior twelve months. Washington uses the current year and the prior year.

Then write the date you crossed the line and the date that state’s page says collection starts. Those two dates are the gap where invoices can go out untaxed.

Exemptions belong in the same file. The SBA’s examples are food and clothing in many states. Minnesota’s resale path is the certificate. A product that is exempt in your home state can be taxable at the destination. Check the destination page. This article does not list every exemption.

Pitfalls that leave you holding the state’s share

• One threshold copied into every state. The three state pages above would give you three different answers.
• An old dollar list. The 2019 SCORE article is the wrong source for a current limit.
• Marketplace sales left out of the total because the platform charged the customer.
• A cart rate treated as the amount you owe. Washington says you owe the correct tax even when the invoice was short.
• A state-only total in a state that uses local rates. The SBA includes local sales tax. Texas and Washington both look past the state name.
• A home-state habit of “we have no sales tax” applied to every ship-to state. The SBA says some states and localities have none. Others do.
• Physical presence ignored because the dollar line is unmet. Washington and the Texas remote-seller definition both put physical presence in a different bucket. SCORE says a store or an office or a warehouse or a person soliciting sales can be enough.

There is a tradeoff in fixing this after the invoices went out. Registering and collecting on time keeps the tax in the price the customer pays. Discovering a missed state after the fact can leave you with the Washington problem. You owe the tax the invoice never collected. The cash is gone. The return is not.

A month-end check

1. Total ship-to dollars and transaction counts for each state where you sold.
2. Mark marketplace sales and whether that platform collects there.
3. Compare each total with that state’s page. Do not reuse a neighboring state’s line.
4. If you are over the line, write the date that page says collection starts. Register before that date.
5. Separate the tax you charged from the sale price on the invoice and in the books.
6. Before you file the state return, compare the tax you charged with the tax the return computes. Washington’s rule is the reason. A short invoice does not shrink the tax.

QuickBooks Online is one place to keep the ship-to state and the tax amount on the sale. It does not decide nexus. It does not pick the local rate. You do, from the state page.

When the month is closed in QuickBooks Online, read the totals by state before you spend them. Multi-state tax tracking is that reading. The customer paid you an amount that may belong to a revenue department. The records are how you keep your part of the sale.