How to Get a Tax ID Number in Mississippi for a New Business

Which tax ID does a new Mississippi business need?

For most new Mississippi businesses, “tax ID number” can refer to two different identifiers: a federal Employer Identification Number (EIN) and one or more Mississippi Department of Revenue account numbers. These numbers are not interchangeable.

The IRS issues the nine-digit EIN, which serves as a federal tax ID for businesses and other entities. A business with employees needs an EIN, as do entities such as partnerships, LLCs, and corporations. An EIN is also required for specified employment, excise, alcohol, tobacco, firearms, and nonresident-alien withholding taxes.

Mississippi tax registration is a separate step. An entity operating in Mississippi may be liable for state taxes and should register with the Mississippi Department of Revenue (DOR). Most new state tax accounts can be registered through the Taxpayer Access Point (TAP), although online availability varies by tax type.

The DOR requests the business’s federal EIN, also called an FEIN, during state registration, but it assigns a separate account number to each Mississippi tax account. In particular, a Mississippi withholding account has its own unique eight-digit number rather than using the FEIN.

The practical order for many new businesses is therefore:

1. Establish the business entity, if applicable.
2. Apply for the federal EIN.
3. Register for each Mississippi tax account that applies to the business’s activities.
4. Keep the federal and state numbers labeled separately in the business’s records.

Eligibility and information to prepare

If the business will be an LLC, partnership, corporation, or tax-exempt organization, form it through the state before requesting its EIN. The IRS advises completing the state formation first because applying before the entity is formed may delay the EIN application.

A sole owner should first determine whether an EIN is required by the business’s employment, entity, or tax circumstances. Even when discussing a business generally, avoid assuming that one registration automatically creates all federal and Mississippi tax accounts.

Information for the federal EIN application

Before beginning, organize the information that identifies the business and the person responsible for it. This typically means having the business’s legal name, any trade or DBA name it intends to use, mailing and physical addresses, entity type, formation details when applicable, and a clear description of why the EIN is being requested. Also be prepared to identify the responsible party and describe the business’s expected activities.

Eligibility for the IRS online application has specific limits. The principal place of business must be in the United States or a U.S. territory, the applicant must be the responsible party or an authorized representative, and the responsible party must have an SSN or ITIN. A business that does not meet these online conditions may need to use another permitted application method.

Information for Mississippi registration

Prepare the business’s FEIN, legal and trade names, addresses, ownership or officer information, entity details, and a description of its Mississippi activities. It is also useful to identify whether the business will have employees, make taxable sales, purchase goods for resale, or conduct activities associated with another DOR-administered tax.

Those activity details matter because Mississippi tax accounts are registered separately. A business examining sales-tax obligations can review the Mississippi State Sales Tax Number overview and the Mississippi State Sales Use Tax Number Identification Application guide for additional context.

How to get the numbers

1. Complete the entity formation first. If the business is an LLC, partnership, corporation, or tax-exempt organization, complete its Mississippi formation before applying for the EIN. Use the entity’s final legal name and other formation details consistently when preparing the federal application.
2. Confirm who will act as the responsible party. Identify the individual who controls or manages the business and make sure the person submitting the application is the responsible party or an authorized representative when using the online tool. Confirm that the responsible party has an SSN or ITIN if the business intends to apply online.
3. Select one federal application method. EIN applications may be submitted online, by fax, or by mail. Telephone applications are limited to international applicants. The IRS directs an applicant to use only one method for each entity, so do not send a second request merely because another submission is still being handled.
4. Submit the EIN application. Applying directly through the IRS online tool is free. If the online application is approved, the EIN is issued immediately online. Save the resulting confirmation with the business’s permanent records rather than relying on memory or an informal note.
5. Observe the daily issuance limit. The IRS limits EIN issuance to one EIN per responsible party per day. This rule applies across the available request methods, including online, telephone, fax, and mail.
6. Identify the Mississippi tax accounts connected to the business. Review what the business will actually do in Mississippi. Employees, retail or other taxable sales, and other tax-specific activities can lead to different registrations. Entity formation and EIN issuance do not replace this activity-based review.
7. Register applicable state accounts. Most new Mississippi tax accounts can be registered through TAP. Enter the FEIN where requested, but expect the DOR to assign a separate number to each state tax account.
8. Record each identifier by purpose. Label the EIN as the federal identifier and list every DOR account number under its specific Mississippi tax type. This reduces the risk of entering the FEIN where a state account number is requested.

What to do after filing

Keep the EIN confirmation, state formation documents, Mississippi registration records, and tax-account correspondence together in a secure business file. Create a simple reference list showing the legal business name, EIN, each Mississippi account number, and the tax type associated with each number. Limit access to people who need the information for legitimate business administration.

If the business becomes an employer, review the Mississippi withholding registration rule separately. An employer doing or transacting business in Mississippi, or paying specified wages to Mississippi residents or for services performed in Mississippi, must register for a Mississippi withholding tax account through TAP. The resulting withholding number is a unique eight-digit state number, not the federal EIN.

A business making sales should likewise evaluate the state registration connected to those sales rather than treating the EIN as sales-tax authorization. Businesses that buy qualifying goods for resale may also want to understand how to get a resale certificate in Mississippi.

Tax registration also should not be confused with business licensing. Depending on the activity and location, the business may need to evaluate licenses separately. The examples in Business License Requirements in Mississippi: Common Examples can help organize that review without treating a tax number as a license.

Practical examples

A new Mississippi LLC with employees

Suppose an owner forms a Mississippi LLC and plans to hire employees. The owner should complete the LLC formation before requesting the EIN. Because the LLC is an entity listed by the IRS and the business will have employees, it needs an EIN. After receiving the EIN, the employer must address Mississippi withholding registration through TAP if its business and wage connections fall within the DOR rule. The business should record the federal EIN and the separate eight-digit Mississippi withholding account number under different labels.

A corporation selling products in Mississippi

A newly formed corporation should obtain its EIN after completing state formation. It can then use the FEIN when registering applicable Mississippi DOR accounts. If its activities call for a sales-related account, the DOR will assign an account number for that state tax rather than converting the FEIN into the state account number.

A business adding a new activity later

Consider a business that initially obtains an EIN but has no employees. If it later hires workers or begins another activity associated with a Mississippi-administered tax, it should review the registration connected to that new activity. The existing EIN continues to identify the business federally, while the DOR assigns the applicable state account separately. This is why maintaining a tax-account list is more useful than referring to every identifier simply as the business’s “tax ID.”

The key is to match each number to its purpose: form the entity first when required, obtain the federal EIN through one application method, and then register the Mississippi accounts tied to the business’s actual operations.