Key Takeaways

  • An LLC number typically refers to your LLC’s EIN (Employer Identification Number), issued by the IRS.
  • An EIN is required for tax purposes, hiring employees, opening a business bank account, and more.
  • You must form your LLC with your state before applying for an EIN.
  • EIN applications can be submitted online, by fax, mail, or phone (for international applicants).
  • The fastest and most efficient method is through the IRS online application portal, available Monday–Friday.
  • There is no cost to obtain an EIN directly from the IRS.
  • Mistakes in the application process can delay your EIN approval.

One of the steps of forming an LLC is to figure out how to get a tax ID number for an LLC. A tax ID number, also known as an “employer identification number,” is used by the Internal Revenue Service (IRS) for federal tax purposes. Every LLC must have its own unique tax ID number.

What is an LLC?

An LLC, or limited liability company, is a type of business structure that is a combination between a partnership or sole proprietorship and a corporation. It features the “pass-through” taxation of a partnership and sole proprietorship, and the personal liability protection of a corporation. These features are what make an LLC so attractive to all types of businesses.

Owners, or “members,” of an LLC are protected against any personal liability for any of the financial debts or legal liabilities of the company. Limited liability protection shields the members’ personal assets from any of the LLC’s creditors, and is one of the main reasons why LLCs are the most popular type of business structure in the U.S. Members can be individuals or any other type of business entity, such as partnerships or corporations; there are also LLCs that are just owned by a single person.

An LLC is considered a “pass-through” entity. This simply means that the LLC’s income and losses will pass through to the individual members’ personal tax returns. Thus, the members are only paying taxes on their profits from the LLC one time. Members of an LLC also have the flexibility of choosing how they want the LLC to be taxed. For instance, they can elect to be taxed as a sole proprietorship or an S corporation.

Forming an LLC

LLCs are governed by state law. Therefore, the requirements for forming and maintaining an LLC will vary depending on which state the LLC registers with. If the LLC is going to register in more than one state, it is important that the owners understand the unique requirements of each state in order to fully comply with the law.

There are several steps to forming an LLC, including obtaining a tax ID number. As stated above, each state has its own regulations governing the formation of an LLC. Hence, it is important that the members meet all of these obligations in order to comply with state and federal tax laws.

What is a Tax ID Number and What is it Used For?

A critical step in forming an LLC is to obtain a tax ID number with the IRS. This ID number is essentially like a business’s social security number. It is used by the IRS to identify the business for federal tax and banking purposes.

It should be noted that before an LLC can obtain a tax ID number, it must be formed and registered in a state. To obtain a tax ID number, the LLC owner can apply directly through the IRS website. Any LLC that has two or more members, or has employees, must obtain a tax ID number. If a single-member LLC adds a new member, or hires its first employee, it must also apply for a tax ID number. An LLC with only a single member can use that member’s personal social security number instead.

Do All LLCs Need an EIN?

Not every LLC needs an EIN immediately, but most will at some point. Here's a breakdown:

  • Single-member LLCs with no employees and no excise tax liability can use the owner's Social Security Number (SSN) for federal tax filings.
  • Multi-member LLCs are required to obtain an EIN, even if they don’t have employees.
  • If a single-member LLC hires employees, adds additional members, or elects to be taxed as a corporation, it must obtain an EIN.
  • You’ll also need an EIN to open a business bank account, apply for business licenses, and file certain tax returns.

Even if not required, many businesses obtain an EIN early to streamline operations and separate personal and business finances.

How to Apply for a Tax ID Number

When applying for a tax ID number, the IRS website will ask a series of questions that require knowledge of the business and its owners, such as:

  • Each owner’s social security number
  • The purpose of the filing
  • rejected income, etc.

You can apply for a tax ID number either electronically, by phone, through the mail, or by fax.

After you answer those questions, you will need to designate a “responsible party.” Even if an LLC has multiple members, there can only be one responsible party for purposes of getting the tax ID number.

Once you have completed the required steps, the IRS will send you a confirmation email that will contain the LLC’s tax ID number. In addition, an official confirmation letter sent by the IRS through traditional mail will follow that contains the relevant tax ID documents. The LLC should be sure to keep these in a safe, private place for security purposes.

What Happens After You Receive Your EIN?

Once you obtain your EIN, you can use it immediately for:

  • Opening a business bank account
  • Applying for business licenses and permits
  • Filing tax returns (federal, and possibly state)
  • Hiring employees and processing payroll

Keep your EIN in a secure location and share it only with trusted financial institutions, government agencies, or tax professionals. The IRS will also send an official EIN confirmation letter (CP 575) for your records.

Common Mistakes to Avoid When Applying

Making errors on your EIN application can cause delays or IRS rejections. Watch out for these common issues:

  • Submitting the application before your LLC is officially formed with the state
  • Providing inconsistent information, such as mismatched names or incorrect SSNs
  • Selecting the wrong entity type or tax classification
  • Failing to specify the correct "responsible party"
  • Using non-U.S. characters or symbols, which the system cannot process

To avoid these mistakes, double-check your application and consider seeking legal help if you’re unsure.

Step-by-Step Guide to Completing Form SS-4

If you apply for an EIN by fax or mail, you’ll need to complete IRS Form SS-4. Key items to fill out include:

  • Legal name of the LLC and any trade names
  • Mailing address and physical location
  • Type of entity (LLC, partnership, etc.)
  • Reason for applying (e.g., starting a new business, hiring employees)
  • Name and SSN or ITIN of the responsible party
  • Date the LLC started or will start operations
  • Highest number of employees expected in the next 12 months
  • Business activity and principal line of goods/services

Be sure to review for accuracy. Errors can delay the issuance of your EIN.

Ways to Apply for an EIN

You can apply for an EIN using several methods. Each has different processing times and requirements:

  1. Online (Recommended):
    • Visit the IRS EIN Assistant.
    • Available Monday through Friday, 7 a.m. to 10 p.m. Eastern Time.
    • Only available to applicants whose principal business is located in the U.S. or U.S. Territories.
    • You’ll receive your EIN immediately upon completion.
  2. Fax:
    • Complete IRS Form SS-4 and fax it to the appropriate number based on your state.
    • If you provide a return fax number, you’ll typically receive your EIN within 4 business days.
  3. Mail:
    • Mail Form SS-4 to the IRS. Processing takes about 4 weeks.
    • Use this method only if time is not a factor.
  4. International Applicants:
    • Cannot use the online application.
    • Must call the IRS at 267-941-1099 (not toll-free) Monday through Friday, 6 a.m. to 11 p.m. Eastern Time.

Frequently Asked Questions

  1. What is the difference between an LLC number and an EIN?
    The term “LLC number” often refers to an LLC’s EIN, which is issued by the IRS for tax and identification purposes. Some states also issue a separate state ID or file number during LLC registration.
  2. Can I get an EIN before forming my LLC?
    No. Your LLC must be officially formed and registered with the state before you can obtain an EIN from the IRS.
  3. Is there a fee to get a tax ID number for an LLC?
    No. Applying for an EIN directly through the IRS is completely free.
  4. How long does it take to get an EIN?
    If you apply online, you can get your EIN immediately. Fax applications take about 4 business days, and mailed applications can take up to 4 weeks.
  5. Can I use my SSN instead of an EIN for my LLC?
    Only single-member LLCs with no employees or excise tax obligations may use the owner's SSN. Otherwise, an EIN is required.

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