Key Takeaways

  • A state tax ID number is used for state-level business identification and taxation.
  • Businesses may need a state tax ID number for payroll taxes, sales tax collection, and other regulatory compliance purposes.
  • If a business operates in multiple states, it may need multiple state tax ID numbers.
  • The EIN (Employer Identification Number) is a federal tax ID, while a state tax ID number is issued at the state level.
  • State-specific tax ID lookup resources include state revenue departments and online databases.
  • If a business has lost its state tax ID number, it can recover it through official state agency websites, tax returns, or employer tax documents.
  • The process for obtaining a state tax ID varies, but most businesses apply online through their state’s department of revenue.
  • UpCounsel connects businesses with experienced attorneys for help with tax and business registration issues.

Need to know how to find a state tax ID number for a company? Most types of business entities must have an employer identification number (EIN) in order to open a bank account, receive a business license, file taxes, or apply for a loan. This EIN, also known as a business tax ID number or federal tax ID number, is a nine-digit number that the IRS uses to identify a business.

Regardless of whether your company employs workers, you'll likely need this number for federal tax filing purposes. However, not every company needs an EIN. In some instances, a sole proprietor without any employees can simply use their own social security number.

Some states may require your business to have an EIN prior to completing state tax forms or registering your company within the state. In addition to tax filing, the EIN is used to identify a business in order to process a business license or satisfy other state requirements. For example, California State requires most businesses to have an EIN prior to registering state payroll taxes.

Which States Do Not Require EINs?

Some states do not collect personal income tax, and as a result, do not require an EIN. These states are:

  • Washington
  • Tennessee
  • Alaska
  • Florida
  • Nevada
  • Texas
  • New Hampshire
  • Wyoming
  • South Dakota

When Will I Need My Company's EIN?

There are many situations in which you'll need to provide your company's EIN, including:

  • Processing a company tax payment.
  • Filing a company tax return.
  • Opening a company bank account.
  • Applying for a company loan or credit card.
  • Processing tax forms to independent contractors (Form 1099).

Do All Businesses Need a State Tax ID Number?

Not all businesses require a state tax ID number. Whether your company needs one depends on your business structure and activities, including:

  • Hiring Employees – Businesses with employees must obtain a state tax ID for payroll tax reporting.
  • Selling Taxable Goods or Services – If your business collects sales tax, a state tax ID is required.
  • Operating in Multiple States – If your company operates across state lines, you may need separate state tax IDs for each location.
  • State-Specific Licensing or Permits – Some states require a tax ID for business registration, licensing, or compliance purposes.

Sole proprietors without employees may not need a separate state tax ID and can often use their Social Security Number (SSN) instead.

How Do I Find an EIN?

For a company, an EIN is similar to a social security number for an individual. As such, most companies keep their tax ID numbers private, so you probably won't find it published on the company's website. However, many documents require the number. If you're an employee of a company, look in box B on your W-2 statement. If you're an independent contractor, you can find this number in the Payer's Federal Identification Number box on Form 1099.

If you're an employee of a company and cannot find your company's EIN, you may call or email the Department of Revenue for your state. You'll need to provide your employer's legal company name and any additional required information.

If you have a valid reason to know a business's EIN, you can simply call the business and ask for it. If you are dealing with a small company, you can speak with the company owner or your usual contact person. If you are dealing with a large company, get in touch with the accounts payable department if you need to send an invoice. If you've received an invoice from a company, contact that company's accounts receivable department. This is usually the contact person whose name is printed on the invoice.

If you are providing a product or service to another company and would like to know whether that company qualifies for tax exemption, you can ask your customer for the number. In some situations, this number will appear on a state-issued certificate.

Another option is the Electronic Data Gathering, Analysis, and Retrieval Database, or EDGAR. This free search tool is provided by the Securities and Exchange Commission and is available to the public. You can enter a business name and look up all the associated paperwork. Many of these documents include the business's EIN. However, the Securities and Exchange Commission only deals with publicly traded companies that sell stock on an exchange. Thus, information regarding privately held companies is not available on EDGAR.

How to Apply for a State Tax ID Number

Applying for a state tax ID number varies by state, but the general process includes:

  1. Determine Your State's Requirements – Visit your state’s Department of Revenue website to check registration guidelines.
  2. Obtain a Federal EIN – Most states require businesses to have an EIN before applying for a state tax ID.
  3. Complete the Online or Paper Application – Many states allow online applications, while others may require paper forms.
  4. Provide Business Information – This typically includes your EIN, business entity type, owner details, and business address.
  5. Receive Your State Tax ID – Processing times vary, but many states issue tax IDs immediately or within a few business days.

For specific state-by-state application links, check your state’s official tax agency website.

How to Find a State Tax ID Number

Finding a state tax ID number is essential for businesses handling payroll taxes, sales tax collection, or state-specific regulatory compliance. Unlike the federal EIN, which is issued by the IRS, a state tax ID is assigned by the state’s tax authority. Here’s how you can find it:

  1. Check Business Tax Documents – Review past state tax returns or payroll tax filings, where the state tax ID is often listed.
  2. Look at Employer Tax Filings – If you have employees, your state tax ID should appear on state wage and withholding reports.
  3. Contact the State Tax Agency – Most state revenue departments offer online lookup tools or customer service options to help retrieve your state tax ID.
  4. Check State Business Registration Records – Some states make business tax ID numbers publicly accessible through their Secretary of State or Department of Revenue websites.
  5. Log into Your State's Tax Portal – Many states provide online business portals where registered businesses can access their tax IDs and filing history.

How Do I Recover a Lost EIN?

Companies will keep the same EIN so long as their firm is open unless they reorganize and apply for a new number. You can recover a misplaced or lost EIN by looking up the number on your computer-generated IRS notice associated with the ID number assignment.

If you are unable to use that original paperwork, contact your bank or credit union. These institutions keep your company's EIN on file with the rest of your account information.

If these options are unavailable, you can contact the IRS Business and Specialty Tax Line. You'll need to provide personal information in order to confirm your identity before the department will provide the EIN.

How to Recover a Lost State Tax ID Number

If you have misplaced your state tax ID number, follow these steps to retrieve it:

  • Review Past Tax Filings – Check previous sales tax returns, payroll tax filings, or state-issued tax documents where the number may be listed.
  • Check Employer Tax Forms – If your business has employees, the state tax ID should be on state wage reports or withholding filings.
  • Contact the State Tax Authority – Reach out to the state’s Department of Revenue or Taxation for assistance in retrieving your tax ID.
  • Use Online Business Search Tools – Some states provide online search tools where businesses can look up their registration details.
  • Check Business Bank Records – If your business bank account required a state tax ID for setup, the bank may have it on file.

Frequently Asked Questions

  1. What is the difference between a federal EIN and a state tax ID?
    A federal EIN is issued by the IRS and used for federal tax purposes, while a state tax ID is issued by a state tax agency and is used for state-level business taxes.
  2. Do I need a state tax ID if I am a sole proprietor?
    If you have no employees and do not sell taxable goods, you may not need a state tax ID. Some states allow sole proprietors to use their SSN instead.
  3. Can I look up another business’s state tax ID number?
    Some states allow public access to business tax ID numbers through online business search databases, but many keep this information private.
  4. How long does it take to get a state tax ID number?
    Processing times vary by state. Some states issue the ID instantly online, while others may take several days or weeks.
  5. Where can I find official state tax ID lookup tools?
    Check your state’s Department of Revenue, Taxation, or Secretary of State website for lookup tools and business search databases.

If you need help understanding how to find a state tax ID number for a company, you can post your legal need on UpCounsel's marketplace. UpCounsel accepts only the top 5 percent of lawyers to its site. Lawyers on UpCounsel come from law schools such as Harvard Law and Yale Law and average 14 years of legal experience, including work with or on behalf of companies like Google, Menlo Ventures, and Airbnb.