How to Get an EIN in Mississippi (2026)

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

To get an Employer Identification Number (EIN) in Mississippi, apply directly with the Internal Revenue Service (IRS) for free. The fastest method is the IRS online application, which provides the EIN immediately. Most Mississippi businesses, including LLCs and corporations, need an EIN for federal tax purposes, opening business bank accounts, and registering for state taxes with the Mississippi Department of Revenue through its Taxpayer Access Point (TAP).

What is an EIN and Why Do Mississippi Businesses Need One?

An Employer Identification Number (EIN), also known as a Federal Tax Identification Number, is a unique nine-digit number assigned by the IRS to identify businesses for tax purposes. It functions like a Social Security Number (SSN) for a business entity. Most Mississippi businesses will need an EIN, regardless of their legal structure (e.g., Mississippi LLC, corporation, partnership).

Key reasons a Mississippi business needs an EIN include:

• Federal Tax Filings: Required for filing federal income tax returns, employment tax returns (if you have employees), and other IRS forms.
• Hiring Employees: Essential for any business that pays wages to employees.
• Opening a Business Bank Account: Banks typically require an EIN to open a business checking or savings account.
• State Tax Registrations: The Mississippi Department of Revenue uses the EIN for state tax registrations through TAP, including withholding tax and sales/use tax accounts.
• Forming Certain Entity Types: All corporations and partnerships must have an EIN. Multi-member LLCs also require an EIN.
• Electing S-Corporation Status: If an LLC or corporation elects to be taxed as an S-corporation, an EIN is necessary.

Even if your Mississippi business does not have employees, you may still need an EIN. For example, a single-member LLC treated as a disregarded entity for federal tax purposes generally uses the owner's SSN, but if it elects corporate taxation or has employees, an EIN becomes mandatory. For a comprehensive overview, see how to get an EIN.

When is an EIN Required for a Mississippi Business?

The IRS provides specific criteria for when an EIN is required. For Mississippi businesses, an EIN is generally necessary if the business:

• Has employees.
• Operates 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.
• Has a Keogh plan.
• Is involved with certain organizations, such as trusts, estates, real estate mortgage investment conduits, non-profit organizations, farmers' cooperatives, or plan administrators.
• Is a multi-member Limited Liability Company (LLC).
• Is a single-member LLC that elects to be taxed as a corporation (including S-corporation).

A single-member LLC in Mississippi treated as a disregarded entity and without employees typically does not need an EIN and can use the owner's SSN for federal tax purposes. However, many banks and the Mississippi Department of Revenue may still request an EIN, making it practical to obtain one even if not strictly required by the IRS. For more details, consult the IRS guidance on Do You Need an EIN?

How to Apply for an EIN in Mississippi (Step-by-Step)

Applying for an EIN is a free process conducted directly with the IRS. There are four main methods, with the online application being the fastest. Before applying, ensure your Mississippi business entity has been officially formed with the Mississippi Secretary of State (for example, by filing a Certificate of Formation for an LLC or Articles of Incorporation for a corporation).

1. Gather Necessary Information

Before you begin the application, you will need the following information:

• Responsible Party's Taxpayer Identification Number (TIN): A valid Social Security Number (SSN), Individual Taxpayer Identification Number (ITIN), or an existing EIN. The responsible party is the individual or entity that ultimately owns or controls the entity or exercises ultimate effective control over it. For online applications, the responsible party must have a U.S. TIN.
• Business Name and Address: The legal name of your Mississippi business as registered with the Secretary of State, and its mailing address.
• Type of Entity: Whether your business is an LLC, corporation, partnership, sole proprietorship, etc.
• Reason for Applying: Common reasons include "Started new business," "Hired employees," or "Banking purposes."
• Date Business Started: The month and year your Mississippi business began operations.

2. Choose Your Application Method

The IRS offers several ways to apply for an EIN:

Online Application (Recommended)

This is the fastest method. The IRS online application is available during specific hours (typically Monday to Friday, 7 a.m. to 10 p.m. Eastern Time). You receive your EIN immediately upon successful completion. The responsible party must have a valid U.S. TIN (SSN, ITIN, or existing EIN). Only one EIN can be requested per responsible party per day. Access the IRS Online EIN Application.

Fax Application

Complete Form SS-4, Application for Employer Identification Number. Fax the completed form to the IRS. If you provide a return fax number, you can expect to receive your EIN back within approximately four business days. Confirm the current fax numbers on the IRS website before sending.

Mail Application

Complete Form SS-4 and mail it to the IRS. This is the slowest method, with processing times typically ranging from several weeks. The IRS lists the correct mailing address for domestic applicants on its "Where to File Your Taxes (for Form SS-4)" page.

Telephone Application (International Applicants Only)

International applicants who do not have a U.S. TIN can apply for an EIN by calling 267-941-1099 (not a toll-free number). This service is available Monday to Friday during posted hours. An assistant completes Form SS-4 with you over the phone, and you receive your EIN immediately.

After Getting Your EIN: Mississippi State Tax Requirements

Once you have your EIN, your Mississippi business will use it for federal tax purposes and for state registrations. The primary state agency for business taxes in Mississippi is the Mississippi Department of Revenue (DOR), and most registrations are completed online through its Taxpayer Access Point (TAP).

• Sales and Use Tax: Businesses selling taxable goods or certain services in Mississippi must register for a sales tax permit through TAP. The EIN identifies your business for this account. See our overview of Mississippi sales tax.
• Withholding Tax: If your business has employees, you must register for state withholding tax with the DOR. Your EIN is used for this registration and for filing withholding returns.
• Corporate Income and Franchise Tax: Mississippi corporations are subject to state income and franchise tax, filed under the business's EIN. LLCs taxed as partnerships or disregarded entities generally pass income to their owners, who report it on their personal returns.
• Entity Registration: Formation and annual reports for LLCs and corporations are filed separately with the Mississippi Secretary of State, which is distinct from tax registration with the DOR.

It is crucial to keep your EIN secure and use it consistently across all federal and state filings. For more on Mississippi state tax obligations, visit the Mississippi DOR withholding tax page and the Mississippi business license overview.

Common EIN Application Issues and Solutions

While applying for an EIN is generally straightforward, some common issues can arise:

• Responsible Party Requirements: For online applications, the responsible party must have a U.S. SSN, ITIN, or existing EIN. If not, you must apply by fax or mail, or by phone if you are an international applicant. See what is an ITIN.
• Duplicate EIN Request: If you already have an EIN, you generally do not need a new one unless there is a significant change in your business structure (for example, a sole proprietorship incorporates). The IRS limits one EIN per responsible party per day online.
• Incorrect Business Name: Ensure the business name on your EIN application exactly matches the name registered with the Mississippi Secretary of State. Discrepancies can cause issues with banks and the DOR.
• Application Errors: Double-check all information before submitting. Errors can lead to delays or incorrect EIN assignments.
• Lost EIN: If you lose your EIN, you can find it on previous tax returns, IRS notices, or by contacting the IRS directly. The IRS does not re-issue EINs.

If you encounter difficulties, the IRS website provides extensive FAQs and contact information. For state-level questions about your EIN and tax accounts, contact the Mississippi Department of Revenue.

Frequently Asked Questions

How do I get an EIN for my Mississippi LLC?

Apply for an EIN directly with the IRS. The fastest way is online through the IRS website, which provides the EIN immediately upon completion. You can also apply by fax or mail using Form SS-4.

Is an EIN free in Mississippi?

Yes, an EIN is always free when obtained directly from the Internal Revenue Service (IRS). There are no state or federal fees for an EIN.

Does a single-member LLC in Mississippi need an EIN?

A single-member LLC in Mississippi treated as a disregarded entity by the IRS generally does not need an EIN unless it has employees or elects corporate taxation. Otherwise, it may use the owner's Social Security Number (SSN).

What do I need to apply for an EIN in Mississippi?

You need a valid Taxpayer Identification Number (SSN, ITIN, or another EIN) for the responsible party, the business name and address, and the type of entity. For online applications, the responsible party must have a U.S. TIN.

How long does it take to get an EIN for a Mississippi business?

If you apply online through the IRS website, you receive your EIN immediately after completing the application. Fax applications typically take about four business days, and mail applications can take several weeks.

Do I need an EIN to register with the Mississippi Department of Revenue?

Generally yes. When you register through Mississippi's Taxpayer Access Point (TAP) for withholding or sales tax, the Department of Revenue uses your EIN to identify the business for state tax accounts.

Related

• How to get an EIN (cluster hub)
• How to form an LLC in Mississippi
• Mississippi registered agent requirements
• Mississippi business license requirements
• How to get an EIN in Delaware (sibling)
• How to get an EIN in South Dakota (sibling)
• What is an ITIN?
• Business tax overview
• Mississippi sales tax
• S-Corp vs. LLC

Sources

1. IRS - Employer ID Numbers (General information on EINs).
2. IRS - How to Apply for an EIN (Overview of application methods).
3. IRS - Do You Need an EIN? (Criteria for EIN requirement).
4. IRS - About Form SS-4, Application for Employer Identification Number (Details on the application form).
5. IRS - Apply for an Employer Identification Number (EIN) Online (Online application and hours).
6. IRS - Applying for an EIN by Fax (Fax numbers and processing times).
7. IRS - Applying for an EIN by Mail (Mailing addresses and processing times).
8. IRS - Taxpayer Identification Numbers (TIN) (Information on SSN, ITIN, EIN).
9. IRS - Limited Liability Company (LLC) (Federal tax treatment of LLCs).
10. IRS - S Corporations (Information on S-corp election).
11. Mississippi Secretary of State - Business Services (Mississippi entity formation and filings).
12. Mississippi Department of Revenue - Business Registration (Registering through TAP).
13. Mississippi Department of Revenue - Withholding Tax (State withholding registration).
14. Mississippi Department of Revenue - Sales Tax (Sales tax permit requirement).
15. Cornell Law School Legal Information Institute - Employer Identification Number (EIN) (Legal definition and context).

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 the Mississippi Department of Revenue before acting.