How to calculate sales tax as a remote seller in 2026

If you sell online in 2026, sales tax comes with the territory. States rely on sales tax to fund schools, hospitals, roads, parks, public services, and more.

Since the Supreme Court's Wayfair decision in 2018, they've expected remote sellers to help collect it. The rules have matured a lot since then, but they haven't stopped changing.

Fret not; This page serves as a US sales tax guide for 2026. As a remote seller, read on to learn how to calculate sales tax this year.

Understanding sales tax basics

Sales tax is a consumption tax charged on the sale of goods and certain services. However, it's equally important to understand the sales tax by state.

For example: You're a remote seller offering TRT online. If you sell testosterone replacement therapy to customers in Texas, California, and Oregon, your sales tax obligations won't be the same.

Texas and California impose statewide (and often local) sales taxes. Once you cross economic nexus rules (thresholds), you may need to collect tax depending on how TRT is classified. In Oregon, however, there's no statewide sales tax, so you generally wouldn't collect sales tax there.

In the U.S., sales tax is administered by states and, in many cases, by local jurisdictions such as counties and cities. For instance:

• 45 states and the District of Columbia have a statewide sales tax.
• Five states don't (Alaska, Delaware, Montana, New Hampshire, and Oregon).
• Alaska doesn't have a state sales tax, but many local jurisdictions do. They coordinate remote seller rules through the Alaska Remote Seller Sales Tax Commission.

Note: The Tax Foundation keeps an up-to-date overview of state rates and structures if you want to check your footprint at a glance. You can also specifically find the Alaska remote sales tax information via this ARSSTC portal.

A quick vocabulary check helps:

• Nexus: A sufficient connection to a jurisdiction that creates an obligation to collect and remit sales tax. Nexus can be created by physical presence (e.g., inventory in a warehouse) and/or by economic activity (e.g., sales volume).
• Destination-based sales tax: Tax is based on the buyer's location. Most states use destination sourcing for remote sales.
• Origin-based sales tax: Tax is based on the seller's location. A handful of states use origin sourcing for in-state sellers. But for remote sellers, the destination usually determines the tax obligations.

Sales tax nexus in 2026

The economic nexus is the big one for remote sellers.

After South Dakota v. Wayfair, Inc., states can require out-of-state sellers to collect sales tax based on their economic activity in the state, even without physical presence.

If you cross a threshold (usually a certain dollar amount of sales into the state and, in some states, a number of transactions), you'll have to register and collect sales tax.

The high-level picture in 2026:

• Every state with a statewide sales tax has an economic nexus rule. Many use a $100,000 sales threshold, while some set it at $500,000. A growing number emphasize revenue-only thresholds over transaction counts. The Tax Foundation maintains a state-by-state list.
• Marketplace facilitator laws are widespread. If you sell through marketplaces like Amazon or Walmart, those platforms often collect and remit on your behalf where required. Rules vary, so confirm with the National Conference of State Legislatures or NCSL's marketplace facilitator collection requirements.
• Home-rule and local complexities are getting easier. For instance, Colorado's SUTS portal and Louisiana's Remote Seller Commission have centralized many local filings. These reduce friction for remote sellers.

Case in point: If you sell email newsletter templates nationwide and generate $120,000 in sales to customers in a single state, you may trigger that state's economic nexus threshold, even if you have no physical presence there.

After South Dakota v. Wayfair, Inc., crossing that revenue threshold alone can require you to register and collect sales tax. And if you sell those same templates through marketplaces like Amazon, the platform may collect on your behalf, but you may still need to monitor your total sales for nexus purposes.

Internationally, the concept is similar. Authorities care about where the customer is and whether you've crossed a threshold or made any sales at all. For instance:

• The EU uses VAT with One Stop Shop (OSS) and Import OSS (IOSS) systems to simplify cross-border e-commerce.
• Canada has rules for cross-border digital and platform sales via its GST/HST for digital-economy businesses.

Determining if you have nexus

Think of Nexus as a checklist you revisit often. Review your nexus status quarterly, not annually.

States constantly update their thresholds and regulations, and what didn't trigger nexus three months ago might today. Set up alerts for the states where you're approaching thresholds. It's far easier to prepare for compliance than to fix it retroactively.

A clear, simple, and repeatable process:

• Map where you sell. Pull a report of your last 12 months of sales by ship-to state (and country).
• Check thresholds. Compare your totals to each state's economic nexus rules. Common examples:
  • $100,000 in gross sales in the state (many states)
  • $500,000 in CA, NY, and TX
  • Some states still mention 200 transactions as a trigger (though many have moved away from it)
• Consider physical presence. Inventory in a third-party warehouse, employees, contractors, trade show attendance, or a leased office typically creates nexus even at low sales volumes.
• Include marketplaces. Marketplace sales may count toward economic thresholds, even if the marketplace collects the tax. States differ here, so verify before assuming.
• Don't forget local rules. Alaska localities and certain home-rule jurisdictions (like some in Colorado) may have separate requirements, though portals like SUTS and ARSSTC help address them.
• Reassess quarterly. Rolling 12-month windows are common, and seasonal spikes can push you over a threshold.

If you sell internationally, repeat this logic with VAT/GST rules. For the EU, OSS/IOSS can streamline registrations, as cited above.

How to handle sales tax as a remote seller

Once you've established nexus, compliance becomes an operational process. As a remote seller, you'll need to register properly, calculate tax accurately at checkout, as well as file and remit on time.

That said, here's how to handle each step without creating unnecessary risk or friction.

1. Collecting sales tax

Once you determine you have nexus, your next steps are fairly standard:

• Register for a permit. Visit the state's Department of Revenue to register. The Federation of Tax Administrators keeps a directory of state tax agencies. Some states participate in the Streamlined Sales Tax registration system, which lets you register once for multiple states.
• Set up your checkout. Configure your e-commerce platform to collect the right tax at checkout for taxable items and taxable jurisdictions. If you sell on marketplaces, confirm whether the marketplace collects and how that affects your own settings.
• Validate tax-exempt customers. Collect and store exemption certificates before you skip tax. Streamlined provides a standardized exemption certificate that many states accept.

Learn from Christopher Skoropada, CEO of Appsvio, who has his fair share of experience selling digital apps to other states. He warns sellers about multi-state compliance pitfalls.

Each state has its own registration requirements, filing frequencies, penalty structures. Don't assume what works in one state applies to another. Some states require registration before your first sale, while others allow a grace period. Understanding these nuances prevents costly penalties and protects your business reputation.

Common mistakes to avoid:

• Collecting before you're registered in a state that prohibits it
• Assuming marketplaces always cover you (they usually do, but not for every product type or every scenario)
• Forgetting local taxes or special tax districts
• Treating shipping the same everywhere (shipping and handling taxability varies)
• Ignoring product taxability (software, digital goods, supplements, and clothing can have special rules)

2. Calculating sales tax

This is the most crucial step in the overall tax equation. As a remote seller, here's the practical side: How to get the right number on each order.

• Confirm the sourcing rule. For remote sellers, tax is almost always destination-based. Use the customer's delivery address.
• Determine the taxability of what you're selling. Is the product taxable? Partially taxable? Exempt? This varies by state, especially for digital goods, SaaS, groceries, clothing, and supplements.
• Find the correct rate. Rates can be a stack (state, county, city, and special district). Use geocoding or certified rate tables tied to the exact delivery address, which can overlap multiple jurisdictions.
• Define the taxable base. Understand whether shipping, handling, gift wrap, or environmental fees are taxable in that state. Discounts generally reduce the taxable base if applied before tax.
• Apply exemptions. If a valid exemption certificate is on file, don't charge tax on qualifying items or customers.

A quick example:

• Order subtotal: $100.00
• Shipping: $10.00 (taxable in some states, non-taxable in others)
• Discount: $10.00 (applies to items, not shipping)
• Destination total tax rate: 7.25%

If shipping is taxable in that jurisdiction:

• Taxable base = ($100 - $10) + $10 shipping = $100
• Tax = $100 x 7.25% = $7.25

If shipping is not taxable:

• Taxable base = $90
• Tax = $90 x 7.25% = $6.53

So, if you don't want to do it manually, consider using Quaderno's sales tax calculator.

Automation helps here, especially once you're selling into multiple states with thousands of rate combinations.

Take it from Matthew Thompson, Founder of OwnerWebs. Having built vacation rental websites, he scaled his operations across all 50 states and saw the difference firsthand.

Automation transformed our sales tax management. We went from spending 20 hours monthly on calculations and filings to under two hours. The key is choosing software that integrates with your existing systems and grows with your business. Start with automation early, as manual processes become unmanageable faster than you think.

3. Filing and remitting sales tax

Collecting is only half the job; filing and remitting closes the loop. Here's what to keep in mind:

• Filing frequency: States assign weekly, monthly, quarterly, or annual filing based on your sales volume in that state. Watch for changes, as high growth can bump you into more frequent filing.
• Deadlines: Many states require returns by the 20th of the month following the reporting period, but it varies. Some offer a small vendor discount for timely filing.
• Zero returns: If you're registered but have no sales, you may still need to file a zero return.
• Consolidation: Where available, use centralized systems like Colorado SUTS or Louisiana's Remote Seller portal to streamline local filings.

Ryan Walton, Program Ambassador of The Anonymous Project, has seen what happens during audits. That's why he recommends proper documentation for tax compliance.

Documentation is your safety net. Keep detailed records of every exemption certificate, every rate change, every filing. Create a compliance calendar with all your filing deadlines across jurisdictions. The sellers who struggle most during audits are those who treated record-keeping as an afterthought.

What happens if you miss? Expect penalties and interest, notices, as well as potential audits. Strategies that help:

• A compliance calendar with automated reminders
• Role-based access so someone can file if your usual filer is out
• Reconciliation workflows that match collected tax to filings by jurisdiction
• Voluntary disclosure programs (VDAs) if you discover past liabilities in a new state.

These can limit lookback periods and reduce penalties. Ask a tax pro or review state guidance before you outreach.

Using sales tax tools and resources for 2026

In 2026, remote sellers need structure behind the scenes.

Many use contract management software to stay aligned with suppliers, couriers, and logistics partners, helping them define roles and reduce operational risk.

That same mindset applies to tax compliance. The right digital tools help automate calculations. They can assist you in tracking nexus and keeping multi-state filings under control.

You don't have to build everything from scratch. A few categories to consider:

• Rate and rules engines: Determine taxability and calculate rates by address.
• Exemption certificate management: Collect, store, validate, and renew certificates.
• Registration and filing support: Think of bulk registrations, return preparation, e-filing.
• Analytics and alerts: Consider nexus threshold monitoring and anomaly detection.
• Developer-friendly APIs: Perform real-time calculations at checkout and invoicing.

Take Quaderno's robust tax compliance platform for instance, specifically designed for e-commerce businesses. It enables you to manage sales tax (including VAT and GST), from tax registration to tax collection and calculation up to tax filing and invoice submission.

Final words

Getting sales tax right in 2026 comes down to a rhythm. Monitor your obligations, register from the outset, calculate correctly at checkout, and file on time. Sure, the rules still shift; However, you just need a steady process and the right tools.

As such, think beyond pure compliance. Build sales tax considerations into your pricing strategies and market expansion plans. When evaluating new markets, factor in the compliance costs and complexity. Some states offer voluntary disclosure programs that can reduce past liabilities. These opportunities can save significant money when expanding into new territories.

Treat sales tax like part of your operating system, not just an afterthought. That's how you stay compliant without slowing your growth. Leverage Quaderno's tax compliance software for your online business—Sign up today to start your seven-day free trial!

Author's bio: Thanks to Brooke Webber for sharing her expertise and writing this article for us! Brooke brings five years of experience writing on HR, tax compliance, workplace psychology, and financial operations, helping businesses align people strategies with practical finance insights.