Key takeaways
- Sales tax rules vary by state: Nexus can be triggered by physical presence or sales volume—so online sellers must track where they owe tax.
- Automation prevents costly errors: Regularly updating tax software ensures accurate calculations and compliance with changing state laws.
- Compliance is ongoing, not one-time: From registration to remittance, businesses must review obligations regularly as sales and regulations evolve.
In short: Online retailers often get US sales tax wrong by collecting only in their home state. Since the 2018 Wayfair ruling, economic nexus can create obligations in other states. Common mistakes include ignoring product and digital taxability, relying on platforms, skipping permits and failing to remit tax on time.
Managing sales tax can be a minefield for online retailers. State rules keep changing. Working out where and how to collect sales tax is complex, especially once you expand beyond your home state. Mistakes can lead to hefty fines, audits and damage to your reputation. Here are the 10 mistakes e-commerce owners make most often, and how you can avoid them.
1. Does sales tax only apply in your state?
No, sales tax does not only apply in your home state. You are often responsible for collecting sales tax in any state where you have nexus. "Nexus" is a legal term for the connection between a business and a state.
Traditionally, a physical location created nexus, such as an office, warehouse or employees in a state. However, thanks to recent legislation, sales volume or revenue can also establish nexus.
Pro tip: Use nexus-checking software or consult a tax advisor to see where you may have a tax obligation. This can vary significantly by state.
2. How do economic nexus rules work?
Economic nexus rules let states make out-of-state sellers collect sales tax once they pass certain thresholds. The Supreme Court allowed this with the 2018 Wayfair ruling. The rules vary by state.
For example, some states require sales tax collection once annual sales exceed $100,000 or 200 transactions within the state. Each state sets its own thresholds. So you need to stay informed on where you qualify for economic nexus.
Pro tip: If you are scaling up or already sell a lot across several states, consider automating sales tax tracking and reporting. Some e-commerce sales tax software solutions can track state thresholds. They can notify you when you reach economic nexus in a new state.
3. Are all products taxed the same?
No, sales tax does not apply to all goods and services in the same way. Each state decides which products are taxable and which are not. Some states don't tax certain items, like clothing, groceries or prescription drugs, while others do.
Some states also apply different tax rates to specific categories of goods or services. This can confuse sellers with diverse product ranges.
Pro tip: Identify product-specific tax rates in each state where you operate. Tax compliance software can often assign the correct rates based on product categories, so you collect the right amount.
4. Do digital products need sales tax?
Yes, many states now tax digital products like ebooks, online subscriptions and even streaming services. Digital goods are a growing part of online sales, and sellers often believe they are exempt. For example, Texas and Washington state tax digital goods, while others may impose partial or conditional taxes.
Pro tip: Check the sales tax rules on digital products for each state where you have nexus. The details matter. Some states only tax certain types of digital content, while others tax it more broadly.
5. Why should you update tax software regularly?
You should update tax software regularly because sales tax rules, rates and exemptions change all the time. States modify their laws to capture tax revenue from e-commerce. Outdated sales tax software can calculate tax wrongly, which could cost you thousands in fines and penalties.
Many states adjust their tax rates each year. Some make mid-year changes that are easy to miss.
Pro tip: Make sure your sales tax software or e-commerce platform auto-updates tax rates. This can save you from unexpected tax errors and reduce manual monitoring.
6. Do platforms automatically collect online sales tax for you?
Not always. Many sellers think e-commerce platforms, like Shopify or Amazon, automatically collect all necessary sales tax for them. These platforms may offer sales tax tools, but you often need to enable and configure them correctly.
Some platforms might also cover only certain states or require separate registrations. That leaves you responsible for the setup.
Pro tip: Check your platform's tax settings for each state where you have nexus. Manually confirm that all relevant states and rates are enabled. This helps you stay compliant across your sales channels.
7. How is sales tax different from VAT?
Sales tax is collected at the point of sale, while VAT (Value-Added Tax) is added to a product's price throughout the supply chain. VAT often comes with different registration and reporting requirements. This can confuse businesses that sell internationally.
For example, if you sell to EU customers, you need to know how VAT applies to your goods. You must also register for VAT in each country where you exceed sales thresholds.
Pro tip: Use VAT software with international tax settings, or consult a tax professional. They can help you tell VAT apart from sales tax in cross-border sales. This matters most if you plan to scale into global markets.
8. When do you need a sales tax permit in a new state?
You need a sales tax permit as soon as you establish nexus in a new state, before you start collecting sales tax. Nexus can come from physical or economic presence. Collecting sales tax without a permit is illegal and can lead to penalties.
Crossing an economic nexus threshold does not automatically authorize you to collect tax. Registration is a separate and essential step.
Pro tip: Plan for registration in states where you are approaching economic thresholds. Acting early can prevent delays and help you avoid non-compliance issues.
9. Is sales tax a set-it-and-forget-it task?
No, sales tax is a moving target for online sellers. As your business grows, your tax obligations change too. States keep adjusting nexus rules, introducing new tax laws and changing tax rates. An e-commerce business that starts by shipping only locally may later reach nexus thresholds in several states.
Pro tip: Review your nexus and tax obligations regularly, ideally every quarter. If your e-commerce software tracks nexus thresholds, review its reports. Then adjust your processes so you collect tax wherever required.
10. What happens if you don't remit sales tax collected?
If you don't remit collected sales tax on time, you can face costly penalties and interest. Collecting sales tax from customers is not enough. You must also pay it to the right state tax authorities by their deadlines.
Each state has different filing requirements. Late payments or missing tax returns can also lead to audits, which can cause a chain of problems for your business.
Pro tip: Set calendar reminders or use software to track remittance deadlines for each state where you collect tax. Some e-commerce platforms offer automated remittance services that make this simpler.
Conclusion
Understanding sales tax is crucial if you want your e-commerce business to avoid costly mistakes. Know where you have nexus and stay on top of changing tax rules. Taking these steps keeps your business compliant and ready to grow. By avoiding these common errors and using the resources available, you can handle sales tax with more confidence and efficiency.
With a proactive approach, reliable software and ongoing learning, you can set your e-commerce business on a smoother path to sales tax compliance. You also gain a more predictable financial future.
Do you need help with your sales tax compliance? Book a free call with one of our sales tax experts to find bespoke solutions for your business, optimize your tax costs, and reach millions of new potential customers.
How Taxually handles this
Taxually’s LumaTax runs a nexus analysis on your sales, helps you register in the states where you must collect, and prepares and files multi-state sales tax returns, including Canadian GST/HST. LumaTax is currently available to enterprises and accounting firms. For the full workflow, read how to automate US sales tax filing in every state.
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Frequently asked questions
Do I only need to collect sales tax in my home state?
No. You must collect sales tax in any state where you have nexus—a business connection that can be established through a physical presence or by exceeding a state’s sales or transaction threshold.
Are digital products subject to sales tax?
Yes, in many states. Digital goods such as ebooks, subscriptions, and streaming services are taxable in several jurisdictions, though the rules and rates vary by state.
Does my e-commerce platform handle sales tax automatically?
Not always. Platforms like Shopify or Amazon may provide tools for tax collection, but you’re responsible for enabling and configuring them correctly in each state where you have obligations.
What happens if I collect sales tax without registering?
Collecting tax without a valid sales tax permit is illegal and can lead to fines or audits. Always register with the state tax authority before collecting any sales tax.
How can I avoid sales tax compliance errors?
Use automated tax software that updates rates in real time, track your nexus thresholds regularly, and file and remit taxes by each state’s deadline to stay compliant.
