Mississippi lesson 4 of 6
Get an EIN and register with Mississippi Revenue
The EIN identifies your LLC to the IRS and to banks. Separately, most active Mississippi LLCs also register with the Department of Revenue for state tax purposes.
Applying for the EIN
Apply for free directly on the IRS website once your Certificate of Formation is approved. If the responsible party has a US social security number or ITIN, the EIN is issued immediately online; otherwise the application goes in on Form SS-4 by fax or post.
Registering with Mississippi Department of Revenue
Register through the Department of Revenue's Taxpayer Access Point if you sell taxable goods or services, since you will need a sales tax permit before making taxable sales, and again if you have employees, since you will need to register for withholding tax. This registration is separate from both the EIN and the Secretary of State filing.
Opening the account
Take the filed Certificate of Formation, the EIN confirmation letter, an operating agreement if you have one, and identification for signers and significant owners. Route all business income and expenses through this account, since mixing personal and business funds is one of the most common reasons courts disregard an LLC's liability protection.
Key takeaways
- The EIN is free and issued by the IRS.
- Department of Revenue registration is separate from the EIN and is needed for sales tax or withholding.
- Keep business and personal funds in separate accounts.
Official sources
Or let us file your Mississippi LLC for you
Everything above is yours to use for free. If you would rather hand it over, we prepare and file the Certificate of Formation, act as your registered agent, and track your ongoing deadlines.
Last reviewed: September 2026 - reviewed by Gullia Filing Legal & Formation Team