You’ve started making sales in other states, and suddenly tax obligations get complicated. Your friend’s accountant mentioned “nexus,” another business owner said you need to file in multiple states, and you’re wondering if you’re already out of compliance. If you’re a Florida-based small business selling across state lines, understanding what is sales tax nexus—and when it applies to your business—is one of the most common oversights that trips up growing companies. This article walks you through the real meaning of nexus, how it determines where you owe sales tax, and the mistakes that cost time and money when ignored.
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Does this apply to your business in Florida?
Sales tax nexus means your business has a sufficient presence in another state that requires you to collect and remit sales tax there. According to the Florida Department of Revenue, nexus can be triggered by having a physical location, employees, inventory, or a level of economic activity in a state. If you’re a Florida business shipping products to customers out of state or operating in multiple states, you likely have nexus in those states and must collect and remit sales tax.
How the rate works
Each state sets its own sales tax rate, and each county within a state may add its own surtax. Florida applies a base state rate of 6 percent, and counties can impose additional surtaxes on top of that. The combined rate varies by county where the sale occurs or where the business is located, depending on the type of transaction and the product sold. Because rates change and vary widely across jurisdictions, you’ll want to check the current rate for each state where you have nexus. The Florida Department of Revenue website provides tax rates for Florida counties, and the IRS maintains resources for federal tax guidance; multistate tax calculators and each state’s department of revenue website give you the exact combined rate for your destination.
How to file step by step
Filing sales tax becomes more complex when you have nexus in multiple states. Each state has its own filing deadline, form, and portal. For Florida filings, the state uses Form DR-15 (Sales Tax Return), which you typically file by the 20th of the month following the reporting period. The form walks you through total sales, taxable sales, tax collected, and any adjustments. When you have nexus in other states, you’ll need to follow that state’s filing process, which often mirrors Florida’s structure but uses different forms and payment methods.
Start by identifying which states you have nexus in—this is where understanding nexus rules and reviewing your sales activity becomes critical. For each state, visit that state’s department of revenue website to get the current filing form, deadline, and rate. Enter your sales by category (taxable vs. nontaxable), apply the correct rate or rates, and file by the deadline. Many states now allow online filing, and some require electronic payment. Missing even one state’s filing deadline can result in penalties and interest, so mark each one on your calendar or set reminders in your business accounting platform.
Common mistakes
Mistake 1: Assuming you don’t have nexus because you don’t have an office out of state. Nexus doesn’t require a physical storefront. If you ship products to a state regularly, store inventory there, have employees making sales calls there, or generate significant sales to customers in a state, you likely have nexus. Many growing businesses think “remote sales” are tax-free—they’re not if you meet the state’s economic threshold or have a physical presence. The fix: Audit your sales by state and shipping address, and research the nexus rules for states where you generate consistent revenue.
Mistake 2: Filing only in Florida and ignoring other states. Small businesses often focus on their home state and forget that multistate sales trigger other states’ collection obligations. This creates gaps in compliance and leaves unpaid tax liability on the books. The fix: Document where you’re selling, set up a filing tracker for each state, and file on time. Many states share data and reconcile filings, so missing a state filing will be noticed eventually.
Mistake 3: Not understanding which products and services are taxable in each state. Florida’s general rule is that services are not taxable unless specifically listed in statute, and tangible personal property is taxable unless specifically exempt. Other states have different rules. A service you don’t charge sales tax on in Florida might be taxable in another state. The fix: For each state where you have nexus, research that state’s taxability rules for your specific products and services, don’t assume Florida rules apply everywhere.
Mistake 4: Mixing up filing deadlines and missing them. Each state has its own deadline, and they’re often different. You might file Florida by the 20th but Missouri by the 15th. Missing even one deadline invites penalties and notice letters. The fix: Create a filing calendar with all states’ deadlines, set reminders at least one week before, and use a centralized system to track what’s been filed and what’s pending.
Frequently Asked Questions
What exactly is sales tax nexus?
Nexus is the threshold of business activity that connects you to a state for tax purposes. Once you have nexus in a state, you must follow that state’s sales tax laws. It can be triggered by physical presence (an office, warehouse, or employees), economic activity (consistent sales to customers there), or affiliates operating in the state. Each state defines the threshold differently.
Do I have sales tax nexus if I’m a Florida business selling to customers in other states?
Not automatically. You have nexus in another state if you meet that state’s threshold for presence or economic activity. Simply having an online store and shipping nationwide doesn’t automatically create nexus in every state. However, if you have regular sales to a specific state, ship inventory there, or have any physical presence there, you likely have nexus and must file in that state. Review each state’s rules to be sure.
What’s the difference between sales tax and use tax?
Sales tax is collected by the seller at the point of sale; use tax is paid by the buyer on purchases they made without sales tax being collected. If you’re a Florida business that buys equipment out of state without paying sales tax, you owe Florida use tax on that purchase. As a seller, you collect sales tax from customers; the customer’s obligation to pay use tax only kicks in if you don’t collect sales tax.
How do I know what rate to charge in another state?
Each state and county has its own combined rate. Visit the other state’s department of revenue website for the current rate, or use a multistate sales tax calculator. Rates change, so don’t rely on rates from last year. When in doubt, check the state’s official website or call their tax helpline. Charging the wrong rate creates audit risk, so accuracy matters.
What happens if I don’t file sales tax in a state where I have nexus?
Missing filings can result in penalties, interest, and notice letters from the state. States now share sales data, and many reconcile filings across businesses, so non-compliance is becoming easier to detect. If you discover you’ve missed filings, contact that state’s department of revenue about a voluntary disclosure or amended filing—addressing it early is better than waiting for an audit notice.
This article is for general educational purposes and isn’t a substitute for advice from a licensed CPA or tax attorney. Rules vary by jurisdiction and change over time—always confirm current requirements with the Florida Department of Revenue or your advisor.
Growing across state lines is exciting, but tax compliance can’t lag behind sales. The real habit that protects you: Know where you have nexus, file on time in every state, and use a reliable system to track deadlines and filings. If multistate compliance feels overwhelming, a CPA familiar with your business can help you set up a filing process and calendar. Your business is built on sales—make sure your tax filing keeps pace.
For the Florida-specific rules behind this, our Florida sales tax guide breaks down rates, deadlines, and filing steps county by county.