The Complete Guide to B2B Sales Tax, Nexus, Resale Certificates and Exemptions in the United States
If your business sells products or services to other businesses in the United States, one question eventually becomes unavoidable:
Do you have to charge sales tax on B2B transactions?
The answer is not simply yes or no.
A sale between two businesses is not automatically exempt from state sales tax. The tax treatment depends on what is being sold, where the transaction is sourced, whether the seller has a sales tax obligation in that state and whether the buyer qualifies for a valid exemption.
This is particularly important for:
- B2B companies
- Wholesalers
- Manufacturers
- SaaS businesses
- Software companies
- Digital businesses
- E-commerce sellers
- Service providers
- Foreign businesses selling to U.S. customers
A mistake can be expensive. If a business fails to collect sales tax when required, the seller may face tax assessments, interest and penalties. On the other hand, charging tax unnecessarily can create customer disputes and administrative problems.
This guide explains how B2B sales tax works in practical terms.
Important: U.S. sales tax is primarily governed at the state and local level. Rules differ between jurisdictions and can change. This article provides general information and should not replace professional tax advice for a specific transaction.
Quick Answer: Does B2B Have to Charge Sales Tax?
Yes, sometimes.
A B2B seller may need to charge sales tax when:
- The seller has a sales tax collection obligation in the relevant state.
- The product or service being sold is taxable under that state’s law.
- The transaction is sourced to that state.
- The buyer does not qualify for an exemption, or the seller does not have the documentation needed to support the exemption.
The fact that the buyer is a company, LLC, corporation or other business does not automatically make the transaction tax-free.
The most important distinction is usually this:
Is the buyer purchasing the product for its own use or for resale?
A retailer buying inventory for resale may qualify for a resale exemption.
A marketing company buying laptops for its employees is generally the final user of those laptops.
Both transactions are B2B.
But the sales tax treatment may be completely different.
Do You Need to Charge Sales Tax? Use This 60-Second Test
Before treating a B2B sale as taxable or exempt, work through these questions.
Question 1: Do you have nexus in the relevant state?
No or uncertain: You may not currently have a collection obligation, but you should review physical and economic nexus rules.
Yes: Continue to Question 2.
Question 2: Is what you are selling taxable?
Consider whether you are selling:
- Physical products
- Digital products
- Software
- SaaS
- Equipment
- Data services
- Professional services
- Other taxable services
Not taxable: You may not need to collect sales tax on that transaction.
Taxable: Continue to Question 3.
Question 3: Does the buyer qualify for an exemption?
Possible exemptions may include:
- Resale
- Manufacturing
- Government purchases
- Qualifying nonprofit purchases
- Direct pay arrangements
No: Sales tax may need to be charged.
Yes: Continue to Question 4.
Question 4: Do you have valid supporting documentation?
A customer simply saying, “We are tax-exempt” is not always enough.
Depending on the transaction and state, you may need:
- A resale certificate
- An exemption certificate
- A direct pay permit
- Other state-required documentation
The Basic Rule
Nexus + taxable transaction + no valid exemption generally means sales tax collection may be required.
That is the simplest framework for understanding B2B sales tax.
Why B2B Sales Are Not Automatically Tax-Free
One of the biggest misconceptions about U.S. sales tax is that sales between businesses are automatically exempt.
They are not.
Sales tax generally focuses more heavily on the transaction and the use of the purchased item than on whether the buyer is a business.
Consider these two examples.
Example 1: A Retailer Buying Inventory
A clothing retailer purchases 500 shirts from a wholesaler.
The retailer intends to sell those shirts to its customers.
The transaction may qualify for a resale exemption if the applicable requirements are satisfied.
Example 2: A Company Buying Office Furniture
A consulting company purchases 500 office chairs for its employees.
The company will use the chairs in its own office.
The company is generally the end user.
The fact that the customer is a business does not automatically create a sales tax exemption.
California’s sales tax guidance similarly distinguishes between purchases genuinely made for resale and purchases made for a company’s own use.
The Five-Step B2B Sales Tax Framework
The best way to analyze a B2B transaction is to follow five steps.
Step 1: Determine Whether You Have Nexus
Step 2: Determine Whether the Product or Service Is Taxable
Step 3: Determine Where the Transaction Is Sourced
Step 4: Determine Whether an Exemption Applies
Step 5: Obtain and Maintain Proper Documentation
Each step matters.
Skipping even one can lead to an incorrect tax decision.
Step 1: What Is Sales Tax Nexus?
Nexus is the connection between a business and a state that can create tax obligations.
For many businesses, nexus is the first question they should answer.
You cannot simply assume that your business has no sales tax responsibilities because:
- Your headquarters are located outside the state.
- You have no physical office in the state.
- You only sell online.
- Your customers are businesses rather than consumers.
After the U.S. Supreme Court’s South Dakota v. Wayfair decision, states can impose sales tax collection obligations on certain remote sellers based on sufficient economic activity.
Oregon’s Department of Revenue explains the basic effect of the decision and notes that states have developed rules requiring certain out-of-state businesses to collect tax based on their connection and sales activity.
There are two major types of nexus that businesses should understand.
Physical Nexus
Physical nexus can potentially arise from activities such as:
- Maintaining an office
- Owning or leasing property
- Employing workers
- Storing inventory
- Operating a warehouse
- Having certain representatives or agents in a state
The exact rules differ between states.
For example, a foreign company may believe that it has no U.S. presence because it does not own an American office.
However, inventory stored in a U.S. warehouse or fulfilment center may create a different compliance analysis.
Economic Nexus
Economic nexus generally relates to a business’s sales activity within a state.
Many states have thresholds based on factors such as:
- Gross sales
- Taxable sales
- Number of transactions
However, there is no single nationwide economic nexus threshold.
Businesses should not blindly apply the commonly quoted “$100,000 or 200 transactions” rule everywhere.
States have their own laws, and the applicable thresholds and definitions can differ.
Important for B2B Businesses
B2B sales may count toward nexus calculations.
Do not assume that sales to business customers are automatically excluded when calculating your exposure.
Step 2: Is What You Sell Actually Taxable?
Once you identify a potential sales tax obligation, the next question is:
What exactly are you selling?
This is where many businesses make mistakes.
The U.S. does not have one universal answer for every product and service.
Taxability can differ based on the state and the nature of the transaction.
Physical Products
Tangible personal property is often subject to sales tax unless an exemption applies.
Examples can include:
- Computers
- Furniture
- Equipment
- Machinery
- Electronics
- Tools
- Office supplies
However, a product purchased for resale or another qualifying purpose may receive different treatment.
Services
Many businesses assume services are always exempt.
That is not necessarily true.
States can tax specific categories of services.
Depending on the state, potentially taxable services may include certain:
- Data processing services
- Information services
- Telecommunications services
- Security services
- Repair services
- Maintenance services
Texas, for example, specifically taxes data processing services, subject to applicable rules and exemptions.
This means a business cannot simply say:
“We sell services, so sales tax does not apply.”
The specific service matters.
Step 3: Where Is the B2B Sale Taxable?
Another common mistake is assuming that sales tax is always based on where the seller is located.
That is not always how the rules work.
The location of the transaction can depend on factors such as:
- Where the product is delivered
- Where the buyer receives the product
- Where the service is performed
- Where the customer receives or uses the service
- State-specific sourcing rules
This becomes especially important for:
- Remote sellers
- E-commerce businesses
- SaaS companies
- International businesses
- Companies with customers in multiple states
Example
A company based outside the United States sells physical products to a business customer in Texas.
The company may need to examine:
- Whether it has nexus in Texas.
- Whether the product is taxable.
- Where the product is delivered.
- Whether the buyer qualifies for an exemption.
The seller’s foreign location does not automatically eliminate the need for a U.S. sales tax analysis.
Step 4: When Are B2B Sales Tax Exempt?
A B2B transaction may qualify for an exemption.
However, the exemption usually depends on the specific reason for the purchase.
The most common examples include the following.
1. Resale Exemption
This is one of the most important exemptions for B2B businesses.
A retailer may purchase goods without paying sales tax when the goods are genuinely purchased for resale, subject to applicable state requirements.
Example
A wholesaler sells 1,000 products to an online retailer.
The retailer intends to sell those products to customers.
The purchase may qualify for resale treatment.
The retailer’s status as a business is not the reason for the exemption.
The intention to resell the products is the important factor.
2. Manufacturing Exemptions
Some states provide exemptions for qualifying:
- Raw materials
- Components
- Machinery
- Manufacturing equipment
However, these exemptions are often more complicated than businesses expect.
Not everything purchased by a manufacturer automatically qualifies.
A business should distinguish between:
- Materials that become part of the final product
- Equipment used in manufacturing
- General office supplies
- Items consumed during operations
The exact rules depend on the state.
3. Government Purchases
Qualifying government entities may receive exemptions under applicable laws.
The seller should verify:
- Whether the entity qualifies
- Whether the specific purchase qualifies
- What documentation is required
4. Qualifying Nonprofit Organizations
Some qualifying nonprofit organizations may receive exemptions.
However, nonprofit status alone does not always mean every purchase is automatically exempt.
State-specific requirements and documentation can apply.
5. Direct Pay Arrangements
Some businesses may have authorization to pay certain taxes directly to the relevant tax authority.
In these cases, sellers may need to review the customer’s documentation before deciding whether to collect sales tax.
Step 5: Why Documentation Is Critical
An exemption can be valid in principle but still create problems if the seller cannot properly support it.
This is why documentation is essential.
Depending on the state and transaction, a seller may need to collect:
- A resale certificate
- An exemption certificate
- A direct pay permit
- Other required records
The Streamlined Sales Tax system provides a multistate exemption certificate accepted by its member states, but businesses must still understand each state’s rules because not every state allows every exemption listed on the form.
A Critical Rule for Sellers
Do not assume that:
“The customer asked not to pay tax.”
is enough.
A seller should have a process for determining:
- Who the customer is
- What exemption is being claimed
- Whether the documentation is properly completed
- Whether the exemption makes sense for the transaction
- Where the records will be stored
What Is a Resale Certificate?
A resale certificate is generally a document provided by a purchaser to support the claim that property is being purchased for resale.
It allows the seller, where applicable requirements are met, to treat the transaction as exempt from sales tax.
However, a resale certificate is not a universal permission to buy anything tax-free.
A Simple Example
A retailer purchases 100 smartphones to sell to customers.
The retailer may provide a valid resale certificate to the supplier.
But if the same retailer purchases 20 smartphones for its employees to use internally, those purchases generally should not be treated the same way.
The purpose of the purchase matters.
The Streamlined Sales Tax guidance makes clear that purchasers claiming an exemption must meet applicable state requirements, and sellers should determine whether the appropriate exemption documentation is available.
Can a Seller Accept Any Resale Certificate?
No.
Businesses should be careful.
Different states may have different rules concerning:
- Accepted forms
- Required identification numbers
- Blanket certificates
- Renewal requirements
- Transaction-specific documentation
Some states accept multistate exemption documentation under certain conditions.
Others may require state-specific information.
For example, the Streamlined Sales Tax system states that purchasers may need to provide identification information for the state in which an exemption is claimed and that not every exemption is accepted in every member state.
What Happens If the Buyer Uses a Resale Certificate Incorrectly?
A resale certificate should not be used simply to avoid paying tax on business purchases.
If a purchaser claims an exemption improperly, potential tax liabilities can arise.
Texas tax guidance emphasizes that merely claiming an item was purchased for resale does not automatically establish the exemption. Records and evidence matter.
This is why both buyers and sellers should take exemption documentation seriously.
Do SaaS Companies Have to Charge Sales Tax to Business Customers?
Sometimes.
This is one of the most important areas of modern B2B sales tax compliance.
A common assumption is:
“We only sell SaaS to businesses, so sales tax does not apply.”
That assumption can be dangerous.
B2B status alone does not determine the taxability of SaaS.
The result may depend on:
- The state
- The nature of the software
- How the software is delivered
- Whether the customer downloads anything
- Whether the transaction is treated as software, a digital product or a service
- Whether an exemption applies
Why SaaS Is Complicated
Traditional software might involve downloading a program onto a computer.
SaaS generally provides remote access to software.
States do not necessarily treat these transactions identically.
For this reason, SaaS companies operating nationally should avoid applying one state’s tax treatment to every customer.
A Practical SaaS Example
Imagine a software company selling a monthly subscription to a U.S. business customer.
The company should ask:
- In which state is the customer located for sales tax purposes?
- Does the seller have nexus there?
- Does that state tax the specific software or service?
- Does a B2B exemption apply?
- Does the seller have the documentation required to support the exemption?
Only after answering these questions should the company decide whether tax should be collected.
Texas as an Example of Why Service Classification Matters
Texas demonstrates why businesses should carefully classify what they sell.
The state specifically addresses taxable data processing services and explains how tax and resale treatment can apply to qualifying transactions.
The lesson is not that every SaaS business automatically owes Texas sales tax.
The lesson is that technology businesses must identify exactly what they are selling under each state’s tax rules.
A business should not rely solely on labels such as:
- SaaS
- Platform
- Subscription
- Technology service
The underlying transaction matters.
What About B2B Digital Products?
Digital products can create similar challenges.
A business may sell:
- Downloadable files
- Digital media
- Online databases
- Software
- Digital subscriptions
- Information products
Taxability can differ between states.
A company selling to businesses should not assume:
“Digital means tax-free.”
Nor should it assume:
“B2B means exempt.”
The seller must examine the applicable jurisdiction and transaction.
What If You Sell Services to Other Businesses?
B2B service businesses often have a different risk profile from companies selling physical goods.
Some professional services may not be subject to sales tax in certain states.
But other services may be taxable.
Potentially relevant categories include:
- Data processing
- Information services
- Telecommunications
- Repair
- Maintenance
- Security
Texas specifically identifies several taxable services, illustrating why businesses should analyze the precise service they provide rather than relying on a general assumption about “services.”
What Happens If the Seller Does Not Charge Sales Tax?
This is a critical issue that many B2B sales tax articles fail to explain.
A seller not charging sales tax does not necessarily mean that no tax is due.
In some circumstances, the buyer may have a use tax obligation.
What Is Use Tax?
Use tax generally applies when taxable property or services are purchased without the applicable sales tax being collected.
For example, a business may purchase taxable equipment from an out-of-state seller that does not collect the applicable tax.
Depending on the jurisdiction and transaction, the purchaser may have an obligation to report and pay use tax.
The Streamlined Sales Tax guidance specifically states that when applicable sales tax is not collected and remitted, a customer may be responsible for use tax unless a valid exemption applies.
Why This Matters for Buyers
A business buyer should not assume:
“The invoice had no sales tax, so the transaction was tax-free.”
That may not be correct.
Who Is Responsible if Sales Tax Is Not Collected?
The answer depends on the circumstances and state law.
However, businesses should understand the difference between:
Seller Liability
A seller that was required to collect tax but failed to do so may face:
- Tax assessments
- Interest
- Penalties
- Audit expenses
Buyer Liability
A buyer may have a use tax obligation when a taxable purchase was made without sales tax being collected.
The specific responsibilities depend on the transaction and applicable law.
Real B2B Sales Tax Examples
Example 1: Wholesaler Selling to a Retailer
A wholesaler sells products to a retailer.
The retailer will resell the products to consumers.
Potential result: The transaction may qualify for a resale exemption if applicable requirements and documentation are satisfied.
Example 2: Business Buying Laptops for Employees
A consulting company purchases 50 laptops.
The laptops will be used by employees.
Potential result: The company is generally the final user. Being a business does not automatically create an exemption.
Example 3: Manufacturer Buying Raw Materials
A manufacturer purchases materials that become part of its finished product.
Potential result: A resale or manufacturing exemption may apply depending on state law and the transaction.
Example 4: Manufacturer Buying Office Supplies
The same manufacturer purchases paper and office equipment for its administration department.
Potential result: These purchases may not qualify for the same exemption as materials incorporated into the final product.
Example 5: SaaS Company Selling to Another Business
A SaaS provider sells a subscription to a company in another state.
Potential result: The provider must analyze nexus, state taxability rules, sourcing and any available exemption.
Example 6: Foreign Company Selling to U.S. Businesses
A UK-based company sells products online to customers across the United States.
Potential result: The company’s foreign incorporation does not automatically eliminate potential state sales tax obligations.
The business may need to review:
- U.S. sales activity
- Physical presence
- Inventory locations
- Economic nexus
- Product taxability
- Customer exemptions
This is particularly important for international businesses expanding into the U.S. market.
Do Foreign Businesses Have to Collect U.S. Sales Tax?
Potentially, yes.
A foreign company does not automatically escape U.S. state sales tax obligations because it was incorporated outside the United States.
A foreign business may need to examine its connection with individual states.
Potential factors can include:
- U.S. inventory
- Warehouses
- Employees
- Agents
- Sales activity
- Economic nexus
This creates a major compliance issue for international businesses.
A company can be legally established in the UK, Pakistan, UAE or another country while selling to customers in multiple U.S. states.
That company may still need a state-by-state sales tax analysis.
This is an area where ForeignBusiness.co.uk can provide unique value because many sales tax guides are written only for domestic U.S. businesses.
International companies face additional questions involving:
- Cross-border payments
- Foreign incorporation
- U.S. registrations
- International banking
- State tax compliance
- U.S. market entry
How B2B Sales Tax Rules Differ Between States
There is no single nationwide sales tax rule.
States can differ in how they treat:
- Products
- Services
- Software
- Digital products
- Exemptions
- Nexus
- Documentation
Here are several examples demonstrating why businesses need a state-specific approach.
California
Businesses need to distinguish between purchases for resale and purchases for their own use.
Resale treatment depends on the transaction and appropriate documentation.
Texas
Texas taxes various services, including data processing services under applicable rules.
Resale and exemption documentation can affect how qualifying transactions are treated.
Streamlined Sales Tax Member States
Certain states participate in the Streamlined Sales Tax system.
A multistate exemption certificate can be accepted by member states, but purchasers and sellers still need to understand state-specific requirements.
Oregon
Oregon does not have a general state sales or use/transaction tax, although businesses should remain aware of other applicable taxes and specific rules.
Important Warning
A short state table cannot replace transaction-specific research.
For example, saying:
“Texas taxes SaaS.”
without identifying the exact service or transaction structure can be misleading.
Similarly, saying:
“B2B sales are exempt in California.”
would be inaccurate.
The better approach is to understand what is sold, who is buying it and how it will be used.
What Records Should a B2B Seller Keep?
A strong compliance process should include records relating to:
- Customer identity
- Customer location
- Product or service sold
- Delivery location
- Sales invoices
- Exemption certificates
- Resale certificates
- Direct pay documentation
- Tax collected
- Tax returns filed
For exempt transactions, businesses should ensure that the relevant documentation can be connected to the appropriate customer and transaction.
Poor recordkeeping can turn a legitimate exemption into an audit problem.
What Businesses Should Ask Before Treating a B2B Sale as Tax-Exempt
This checklist is one of the most important sections of this guide.
Before removing sales tax from a B2B transaction, ask:
About the Seller
- Do we have nexus in this state?
- Are we registered where required?
- Are we required to collect sales tax?
About the Transaction
- What exactly are we selling?
- Is it a product, service, software or digital product?
- Where is it delivered or received?
- Is it taxable in that jurisdiction?
About the Buyer
- Is the buyer purchasing for resale?
- Is the buyer the final user?
- Is another exemption being claimed?
About Documentation
- Do we have the required certificate?
- Is the certificate properly completed?
- Does the claimed exemption match the transaction?
- Have we stored the document properly?
This framework can prevent many avoidable compliance mistakes.
Common B2B Sales Tax Mistakes
Mistake 1: “The Customer Is a Business, So It Is Tax-Free”
Incorrect.
Business status alone does not generally determine taxability.
Mistake 2: “We Are an Online Business, So We Have No Sales Tax Nexus”
Potentially incorrect.
Economic nexus rules can create obligations for remote sellers.
Mistake 3: “We Sell Services, So Sales Tax Does Not Apply”
Potentially incorrect.
Some states tax specific services.
Mistake 4: “The Customer Has a Resale Certificate, So We Don’t Need to Check Anything”
Risky.
The seller should follow applicable rules and maintain appropriate documentation.
Mistake 5: “The Seller Didn’t Charge Tax, So the Buyer Owes Nothing”
Potentially incorrect.
Use tax may apply to a taxable purchase where sales tax was not collected.
Mistake 6: Applying One State’s Rules Nationwide
The United States has a fragmented state sales tax system.
A transaction treated one way in one state may receive different treatment elsewhere.
B2B Sales Tax Compliance Checklist for 2026
Before your business treats a B2B sale as taxable or exempt, review the following.
Nexus
- Have we checked physical nexus?
- Have we monitored economic nexus?
- Do our B2B sales count toward relevant thresholds?
Product or Service
- What exactly are we selling?
- Is it taxable in the relevant state?
- Does the transaction involve software or digital products?
Sourcing
- Where is the product delivered?
- Where does the customer receive the service?
- Which jurisdiction’s sourcing rules apply?
Exemptions
- Is the purchase for resale?
- Does a manufacturing exemption apply?
- Is another statutory exemption available?
Documentation
- Have we collected the appropriate certificate?
- Is it complete?
- Does it support the claimed exemption?
- Are records stored securely?
Ongoing Compliance
- Are nexus thresholds monitored regularly?
- Are exemption certificates reviewed?
- Have we checked for changes in state rules?
Frequently Asked Questions
Do B2B businesses have to charge sales tax?
Yes, sometimes. B2B status does not automatically make a transaction exempt. Taxability depends on nexus, the product or service, transaction sourcing and whether a valid exemption applies.
Are all wholesale sales tax-free?
No. A wholesale transaction may qualify for a resale exemption when the purchaser is genuinely buying the products for resale and applicable requirements are met.
Do I need a resale certificate for every tax-exempt B2B sale?
The documentation required depends on the state and the type of exemption. Some transactions may require a resale certificate or other exemption documentation.
Does a resale certificate mean the customer never pays sales tax?
No. A resale certificate generally supports an exempt purchase for resale. The purchaser may collect or pay tax when the product is later sold in a taxable retail transaction.
Are SaaS sales to businesses taxable?
Sometimes. The tax treatment of SaaS can vary between states and may depend on the nature and structure of the service.
Does a foreign business have to collect U.S. sales tax?
Potentially. Foreign incorporation does not automatically prevent state sales tax obligations. Nexus and other state-specific factors must be reviewed.
What if I don’t charge sales tax?
If your business was required to collect tax, you may face potential assessments, interest and penalties. Buyers may also have use tax obligations when applicable tax was not collected.
Are services sold to businesses exempt from sales tax?
Not automatically. Some states tax certain services while others may not.
Does Oregon have B2B sales tax?
Oregon does not have a general state sales or use/transaction tax. However, businesses should understand that other taxes and transaction-specific obligations may still exist.
Final Answer: Does Business-to-Business Have to Charge State Sales Tax?
Yes, a B2B business may have to charge state sales tax.
The fact that both the seller and buyer are businesses does not automatically make the transaction exempt.
The correct answer depends on five critical factors:
- Where the seller has nexus
- What product or service is being sold
- Where the transaction is sourced
- Whether the buyer qualifies for an exemption
- Whether proper documentation supports the exemption
The biggest mistake is looking at a transaction and asking only:
“Is this B2B?”
The better question is:
“Is this a taxable transaction under the applicable state rules, and if not, can we prove why it is exempt?”
For a small local business, the answer may be relatively straightforward.
For a company selling across multiple U.S. states, operating online, selling SaaS or entering the U.S. market from another country, sales tax compliance can become considerably more complex.
The safest approach is to build a system that monitors nexus, classifies products correctly, verifies exemptions and maintains reliable documentation.
Good B2B sales tax compliance is not about charging sales tax on every transaction. It is about knowing exactly when tax applies, when an exemption is legitimate and how to support the decision if your business is ever questioned.
