How to Get an EIN in Arizona (2026)

Fact-checked by the LegalGlass editorial team against primary sources · Published Aug 6, 2026 · Last updated Aug 6, 2026

You can get an EIN for your Arizona business free from the IRS by applying online via the IRS EIN Assistant, by fax using Form SS-4, or by mail. The online application is the fastest method, providing an EIN immediately upon completion. Most Arizona businesses need an EIN to open bank accounts, hire employees, and file federal and state taxes, including the Arizona Transaction Privilege Tax (TPT).

What is an EIN?

An Employer Identification Number (EIN), also known as a Federal Tax Identification Number, is a unique nine-digit number assigned by the Internal Revenue Service (IRS) to identify a business entity. It functions like a Social Security Number (SSN) for individuals but is specifically for businesses. The EIN is crucial for various business activities, including filing federal and state tax returns, opening business bank accounts, and hiring employees. For a comprehensive overview, see What is an EIN?

In Arizona, an EIN is often a prerequisite for state-level compliance. For instance, the Arizona Department of Revenue (ADOR) typically requires a federal EIN for businesses applying for a Transaction Privilege Tax (TPT) license, which is necessary for most businesses selling goods or certain services in the state. Even if not strictly required by federal law, many Arizona businesses obtain an EIN to establish a clear separation between personal and business finances, which is particularly important for entities like Limited Liability Companies (LLCs).

Who Needs an EIN in Arizona?

Most Arizona businesses will need an EIN. The IRS outlines specific criteria for when an EIN is required. Generally, your Arizona business needs an EIN if it:

• Has employees.
• Is structured as a corporation or partnership.
• Files any of these tax returns: employment, excise, or alcohol, tobacco, and firearms.
• Withholds taxes on income, other than wages, paid to a non-resident alien.
• Involves certain types of organizations, such as trusts, estates, real estate mortgage investment conduits, non-profit organizations, farmers' cooperatives, or plan administrators.

For Arizona-specific requirements, an EIN is almost always needed for:

• Arizona LLCs: If your LLC has more than one member, it is automatically classified as a partnership by the IRS and requires an EIN. If it's a single-member LLC, an EIN is required if it has employees or elects to be taxed as a corporation or S-corporation. Even single-member LLCs without employees often get an EIN for banking purposes and to avoid using their SSN for business.
• Arizona Corporations: All corporations, including S-corporations, must have an EIN.
• Arizona Partnerships: All partnerships must have an EIN.
• Sole Proprietors with Employees: If you operate as a sole proprietorship in Arizona and hire employees, you will need an EIN.
• Arizona TPT License: The Arizona Department of Revenue (ADOR) generally requires a federal EIN for business entities when applying for a Transaction Privilege Tax (TPT) license. This license is essential for businesses engaged in selling tangible personal property or certain services in Arizona.

Even if your business doesn't strictly meet the IRS criteria for a mandatory EIN, obtaining one is often beneficial. It helps separate your personal and business identities, which can be important for liability protection and financial management. For more details on federal requirements, refer to the IRS guidance on Do You Need an EIN?

How to Get an EIN for Your Arizona Business

Getting an EIN for your Arizona business is a straightforward process, and it is always free directly from the IRS. There are four primary methods to apply:

1. Apply Online (IRS EIN Assistant) - Fastest Method

The online application is the quickest way to obtain an EIN. The IRS EIN Assistant is available for most entities whose principal business is located in the U.S. The EIN is issued immediately upon successful completion of the application. This method is available during specific IRS operating hours, typically Monday to Friday, 7:00 a.m. to 10:00 p.m. Eastern Time.

• Who can apply: The applicant must have a valid Taxpayer Identification Number (SSN, ITIN, or another EIN) and must be an individual, not an entity.
• Steps:
  1. Visit the IRS EIN Assistant website.
  2. Follow the prompts, providing information about your business, such as its legal name, address, type of entity (e.g., LLC, corporation), and reason for applying.
  3. Review your information carefully before submitting.
  4. Receive your EIN immediately upon successful submission.

Only one EIN can be requested per responsible party per day through the online application. The "responsible party" is the individual or entity who ultimately owns or controls the entity or who exercises ultimate effective control over the entity.

2. Apply by Fax (Form SS-4)

If you prefer to apply by fax, you can complete and fax Form SS-4, Application for Employer Identification Number. This method is typically faster than mailing the form.

• Form: Form SS-4, Application for Employer Identification Number.
• Steps:
  1. Download and fill out Form SS-4 completely. Ensure all required fields are accurate.
  2. Fax the completed form to the IRS. The fax number for businesses located in Arizona (and other U.S. states) is 855-641-6935.
  3. You should receive your EIN by fax within four business days.

3. Apply by Mail (Form SS-4)

Applying by mail is the slowest method but is an option if you cannot apply online or by fax.

• Form: Form SS-4, Application for Employer Identification Number.
• Steps:
  1. Download and fill out Form SS-4 completely.
  2. Mail the completed form to the IRS. The mailing address for businesses located in Arizona (and other U.S. states) is:
     Internal Revenue Service
     Attn: EIN Operation
     Cincinnati, OH 45999
  3. The processing time for mailed applications can be several weeks (typically four to five weeks).

4. Apply by Phone (International Applicants Only)

This method is exclusively for international applicants who do not have a legal residence, principal place of business, or principal office or agency in the U.S. and need an EIN immediately. U.S.-based Arizona businesses cannot use this method.

• Phone number: 267-941-1099 (not a toll-free number).
• Hours: Monday to Friday, 6:00 a.m. to 11:00 p.m. Eastern Time.
• Requirements: The applicant must be authorized to receive the EIN and answer questions about the Form SS-4.

For most Arizona businesses, the online application is the recommended method due to its speed and convenience. For more general information on obtaining an EIN, see How to Get an EIN.

Information Needed for Your EIN Application

Regardless of the application method, you will need to provide specific information about your Arizona business and the responsible party. This typically includes:

• Legal name of the entity: The exact legal name of your LLC, corporation, partnership, or sole proprietorship as registered with the Arizona Corporation Commission (ACC) or as it will appear on official documents.
• Trade name (DBA), if applicable: If your business operates under a different name than its legal name, also known as a Doing Business As (DBA) or trade name.
• Mailing address and physical location: The primary business address in Arizona.
• Type of entity: Specify whether it's an LLC, corporation, partnership, sole proprietorship, etc.
• Reason for applying: Common reasons include starting a new business, hiring employees, or banking purposes.
• Responsible party's name and Taxpayer Identification Number (TIN): This is typically the owner, principal officer, or managing member. For individuals, this will be their SSN or ITIN. For entities, it will be their EIN.
• Number of employees: If you plan to hire employees.
• Business activity: A brief description of what your business does (e.g., retail sales, consulting, manufacturing).
• Start date of business: The month and year your business started or will start.

Ensure all information is accurate and consistent with your business registration documents filed with the Arizona Corporation Commission (ACC) for LLCs and corporations, or your personal records for sole proprietorships. Inaccurate information can lead to delays or issues with your EIN.

Using Your EIN in Arizona

Once you receive your EIN, it becomes a critical identifier for your Arizona business. Here's how you'll typically use it:

• Federal Tax Filings: Your EIN is used for all federal tax purposes, including filing income tax returns (e.g., Form 1120 for corporations, Form 1065 for partnerships, Schedule C for sole proprietors/single-member LLCs), employment tax returns (Form 941), and excise tax returns.
• Arizona Transaction Privilege Tax (TPT) License: As mentioned, the Arizona Department of Revenue (ADOR) requires an EIN for most business entities when applying for a TPT license. This license is essential for businesses selling tangible personal property or engaging in certain services in Arizona. You can apply for a TPT license through the ADOR's online portal.
• Opening Business Bank Accounts: Banks require an EIN to open a business checking or savings account. This is a crucial step for separating business finances from personal finances.
• Hiring Employees: If your Arizona business hires employees, you will use your EIN for all payroll-related activities, including reporting wages to the IRS and ADOR, withholding taxes, and issuing W-2 forms.
• Applying for Business Licenses and Permits: While Arizona does not have a general statewide business license, many specific industries and local jurisdictions require licenses or permits. Your EIN may be requested on these applications.
• Establishing Business Credit: Your EIN is used to build a credit profile for your business, separate from your personal credit. This is important for obtaining business loans, lines of credit, and vendor accounts.

Keep your EIN in a safe and accessible place, as you will need it frequently for various business and tax-related activities. Do not share your EIN publicly, as it is sensitive business identification information.

Common Mistakes to Avoid

When applying for and using your EIN for your Arizona business, be aware of these common pitfalls:

• Paying for an EIN: The IRS provides EINs for free. Avoid third-party websites or services that charge a fee to obtain an EIN for you. You can always get it directly from the IRS at no cost.
• Applying for Multiple EINs: A business generally only needs one EIN. Applying for multiple EINs for the same entity can cause confusion and processing delays with the IRS. If you lose your EIN, you can retrieve it by contacting the IRS.
• Incorrect Entity Type: Ensure you select the correct entity type (e.g., LLC, corporation, partnership) on your Form SS-4 or online application. An incorrect classification can lead to tax issues. For example, an LLC can be taxed as a sole proprietorship, partnership, or corporation, so ensure your EIN application reflects your intended tax classification.
• Using an SSN When an EIN is Needed: While sole proprietors and single-member LLCs without employees can sometimes use their SSN for federal tax purposes, an EIN is often required for state compliance (like the Arizona TPT license) and is generally better for business professionalism and banking.
• Not Updating IRS Records: If your business name, address, or responsible party changes, inform the IRS. While not all changes require a new EIN, keeping your information current is important for receiving official correspondence.
• Confusing Federal and State IDs: An EIN is a federal tax ID. Arizona also has its own identification numbers for state taxes, such as the TPT license number. Do not confuse the two.

By avoiding these common mistakes, you can ensure a smooth process for obtaining and utilizing your EIN for your Arizona business.

Frequently Asked Questions

How do I get an EIN for my Arizona business?

You can get an EIN for your Arizona business free from the IRS by applying online through the IRS EIN Assistant, by faxing Form SS-4, or by mailing Form SS-4. The online application is the fastest method, providing an EIN immediately upon completion.

Is an EIN required for an Arizona LLC?

An EIN is required for an Arizona LLC if it has more than one member, has employees, or elects to be taxed as a corporation. Even single-member LLCs without employees often obtain an EIN to simplify banking and maintain separation from personal finances.

How much does it cost to get an EIN in Arizona?

It costs $0 to get an EIN for your Arizona business. The IRS provides EINs free of charge. You should never pay a third-party service for an EIN, as you can obtain it directly from the IRS at no cost.

What is the fastest way to get an EIN?

The fastest way to get an EIN is by applying online through the IRS EIN Assistant. This method provides your EIN immediately upon successful completion of the application during IRS operating hours.

Do I need an EIN to get an Arizona TPT license?

Yes, an EIN is generally required to apply for an Arizona Transaction Privilege Tax (TPT) license. The Arizona Department of Revenue (ADOR) requires a federal EIN for most business entities when applying for a TPT license, which is necessary for businesses selling tangible personal property or engaging in certain services.

Can I use my Social Security Number instead of an EIN for my Arizona business?

If you are a sole proprietor or a single-member LLC without employees, you may be able to use your Social Security Number (SSN) for certain tax purposes. However, an EIN is generally recommended for all businesses to maintain professional separation, simplify banking, and meet state tax requirements like the Arizona TPT license.

Related

• How to Get an EIN (cluster hub)
• What is an EIN?
• How to Form an LLC in Arizona
• Arizona TPT License Explained
• How to Get an EIN in California (sibling)
• How to Get an EIN in Texas (sibling)
• Business Glossary

Sources

1. IRS - Employer ID Numbers (EINs).
2. IRS - How to Apply for an EIN.
3. IRS - Do You Need an EIN?.
4. IRS - Form SS-4, Application for Employer Identification Number (PDF).
5. IRS - Taxpayer Identification Numbers (TIN).
6. Arizona Department of Revenue (ADOR) - TPT Licensing.
7. Arizona Department of Revenue (ADOR) - Apply for a TPT License.
8. Arizona Department of Revenue (ADOR) - TPT License FAQs.
9. Arizona Secretary of State - LLC Filing Instructions.
10. Arizona Secretary of State - Corporation Filing Instructions.
11. Cornell Law School Legal Information Institute (LII) - Employer Identification Number.
12. Cornell Law School Legal Information Institute (LII) - Disregarded Entity.
13. Cornell Law School Legal Information Institute (LII) - Partnership.
14. Cornell Law School Legal Information Institute (LII) - S Corporation.

LegalGlass provides general information for educational purposes and is not a law firm or a substitute for advice from a licensed attorney or tax professional. Laws, fees, and thresholds change; verify current requirements with the IRS and Arizona Department of Revenue before acting.