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Why Is U.S. Sales Tax So Complex? (Part 1) | TaxValet

Written by Richard Reynolds | Dec 9, 2025 12:02:01 PM

The U.S. market lures in businesses of every size. Its mix of people, industries, regions, culture, and freedom still makes the American Dream feel within reach.

But the U.S. sales tax system can also feel confusing. Rules shift from state to state, and even from city to city, which leaves many business owners confused before they even begin.

In part one of this two-part blog series, you’ll learn why the system feels so tangled and where the pressure points start. Part 2 walks through how to handle that complexity, build a steady process, and feel confident selling in this market.

 

Why the U.S. Sales Tax System Is So Complicated

U.S. sales tax is complicated for a few reasons. Here are the top 3.

 

1. Too Many Jurisdictions, Too Many Rules

Out of 50 states, 45 states collect a statewide sales tax, and 38 let local jurisdictions add their own. 

Together, they create more than 13,000 unique tax jurisdictions, each with its own rates and rules. And while those jurisdictions often overlap on a map, they rarely align in practice.

For example, most states manage both state and local filings under one system, but not all. Some cities have what’s called home-rule authority, giving them full control over their own sales tax administration. They can create local rules, audits, and filing processes.

Denver, Colorado, is a good example. As a “home-rule” city, it audits, collects, and enforces its own rules, separate from the state. That setup means a business might file two different returns for the same sale. One return sends the state tax to Colorado. The other sends the local tax to Denver. It is still one transaction, but it becomes two filings, which adds more work for your team.

For businesses selling nationwide, the volume of returns can pile up fast. A mid-sized retailer could file in thirty states and dozens of localities every month or quarter, each with its own login, due date, and process. 

Order is possible here. Part two explains how your team can create it.

 

2. Products and Services Are Taxed Inconsistently

Thousands of jurisdictions mean thousands of interpretations. Each state decides what counts as taxable, so an item exempt in one place can be fully taxable in another.

For example, in New York:

  • Clothing under $100 is exempt at the state level, but local jurisdictions can still tax it.
  • A sliced bagel, treated as prepared food, is taxable. A whole bagel is not.

Software sales tax interpretations are even trickier:

  • Texas taxes SaaS as a data-processing service.
  • California doesn’t tax SaaS but taxes physical software licenses.
  • Illinois taxes SaaS only if the use happens in-state.
Some states split software into “canned” and “custom” categories, which turns contracts into guesswork.
 
Sales tax rules don’t stay still, either. For example, Washington recently began taxing digital ads, adding another wrinkle to what counts as taxable. Some states roll out changes with little notice, leaving businesses caught off guard when a once-exempt item becomes taxable.
 
The good news? You don’t need to memorize every twist. Part two explains how to set up routines that keep your team ahead of these changes.

 

3. Nexus Rules Changed Everything

Until 2018, a business only had to collect sales tax in states where it had a physical presence. The South Dakota v. Wayfair ruling changed that. The Supreme Court decided states could now also base sales tax obligations on economic activity.

After Wayfair, almost every state quickly passed its own economic nexus laws, with varying thresholds:

  • Most states use a threshold of $100,000, or a 200-transaction threshold (in some cases both). 
  • Several states, like California, Texas, and New York, set higher limits like $500,000. 
  • A few states have no minimum threshold at all, meaning even one sale can create nexus.

Economic nexus isn’t the only nexus trigger. There are various types of nexus that businesses can trigger across states. To learn more, read our guide on the 7 nexus types businesses often overlook.

A simple routine keeps nexus from spiraling, and part two explains how to build that routine.

 
 
 
 

Why Automation Isn’t a Full Solution 

Software can do a lot for your sales tax compliance. It can look up rates, calculate tax on each sale, and remind your team when filings are due. These tools save time and reduce manual work, but accuracy still hinges on how well they’re set up and monitored.

At a very high level, these are some of the common ways that automation could fail you:

  • Incorrect product taxability settings. Software can only apply what it’s told, and one wrong category can ripple through thousands of transactions.

  • Missed nexus triggers. Many tools fail to track physical or economic activity that creates new obligations.

  • Ignored use tax. Most systems don’t handle use tax at all. Use tax is a tax owed when sales tax wasn’t collected on purchases.

  • Integration failures. Connections between platforms can break silently, leaving reports incomplete.

  • Exemption errors. Software can’t always verify certificates or track home-rule rules without careful setup.

These gaps don’t make automation useless. They just show why people still matter in the process. Part two explains how to build that balance.

 

 

The Real Cost of Sales Tax Complexity

As your business grows, sales tax complexity grows with it. The hidden costs often surprise even experienced teams.

  • Time and labor: Large sales volumes, new channels, and more jurisdictions add hours of work for finance and operations teams.

  • Audit exposure: When a state reviews past activity, they can look back several years. That review can reveal missing registrations or unpaid local taxes, and those findings can create balances that climb fast once fees and fines are added.

  • Team strain: Pressure builds when rules shift. Some teams start taxing exempt items to stay safe. Others slow their expansion plans because they worry about missing a requirement.
 
These pressures ease once the right structure is in place. Part two of this series explains how to build that structure so your team can stay confident in this market.

 

 

Complexity Doesn’t Have to Mean Chaos 

The U.S. market is one of the most rewarding places to grow a business, but it comes with a tax system that few can manage alone. 

With the right support, compliance turns from confusion into clarity.

That’s what TaxValet helps create. We act as your Fractional Sales Tax Department. We stay on top of nexus changes, state updates, and product taxability rules. We handle filings accurately and on time. 

Let us help your business find clarity in the chaos, so you can stay focused on enjoying the market.

Get clarity and support today.

 

U.S. Sales Tax FAQs

 

Which country has the most complicated tax system?

The United States is often considered the most complicated. Each state, and sometimes each city, can set its own rules, rates, and definitions. That creates thousands of jurisdictions and taxability interpretations. Many businesses rely on a sales tax service provider like TaxValet to manage this complexity so they can stay compliant with less stress.

 

How to avoid sales tax in the USA?

There’s no real way to “avoid” sales tax if your business has sales tax nexus or sells taxable goods in the U.S. Teams often work with a service like TaxValet to make sure they meet their obligations without guesswork.

 

Who has the highest sales tax in the world?

Hungary holds the record for the highest standard value-added tax rate at 27%. Unlike U.S. sales tax, Hungary’s VAT is managed nationally, not locally, so it’s consistent across the country.

 

Which country has no sales tax?

Several countries don’t charge a national sales tax or VAT, including Hong Kong, the Cayman Islands, and Bahrain. These countries often rely on other forms of taxation to fund public services.

 

Which state has 0 sales tax in the USA?

Alaska, Delaware, Montana, New Hampshire, and Oregon don’t collect sales tax. However, some local jurisdictions in Alaska still charge local sales tax, so “zero” isn’t always truly zero. Many companies use a provider like TaxValet to confirm whether a location is fully tax-free before they make a sale.

 

What city in the U.S. has no sales tax?

Most cities in Alaska, Delaware, Montana, New Hampshire, and Oregon don’t have a local sales tax. In Alaska, though, some smaller cities, like Anchorage, don’t collect local sales tax even though others in the state do. A team like TaxValet helps businesses check these variations so they never assume a rate that is wrong.

 

What is the most tax-friendly state?

New Hampshire and Delaware often rank among the most tax-friendly states. Neither collects statewide sales tax, and both have low income and property tax burdens. Still, the “best” state depends on your type of business and where your customers are located. Many growing companies work with TaxValet to review this as part of their full compliance plan.