1. What Is an EIN?
2. Completing Your EIN Application
3. Do You Need a New EIN?

How long does an EIN number last? Fortunately, an Employer Identification Number (EIN) issued by the IRS never expires. In some cases, however, you will need to apply for a new EIN.

What Is an EIN?

An EIN is a federal tax identification number that most businesses are legally required to possess. For instance, all businesses that have employees must obtain one of these numbers. It's important to understand that even though these numbers are called "Employer Identification Numbers," many businesses without employees will need this identification number. The IRS issues EINs, and they contain nine digits.

When applying for a business bank account, you have to list your EIN. You will also need to include this number on a variety of other documents related to your business:

  • Income tax forms.
  • Annual tax reports.
  • Forms for tax payment.

Completing Your EIN Application

You need to complete and submit IRS Form SS-4 to obtain your EIN. You can download this form from the IRS website. You are not required to pay a fee to acquire your ID number, and you can submit Form SS-4 either by fax or mail. Even if you decide to submit the application online, downloading the form and reviewing the questions it contains is a good idea. On Form SS-4, you will find several questions about your company, including information about your employees, if you have any, and how long your fiscal year will last. One of the most important sections of this form is where you choose the category of your LLC.

Do You Need a New EIN?

If you've already obtained an EIN for your business, your number will last in perpetuity. In some cases, however, you will need to apply for a new ID number. Fortunately, you don't need a new number if you've only made small changes to your business. When your business undergoes major changes, you will need to request a new tax ID. Changing the name of your business or relocating to a new address does not require a new number.

When you apply for your new EIN, you may need to file additional paperwork on top of Form SS-4, depending on the nature of your company. Every type of organization has different rules for ownership transfers, so you should be sure to learn the rules for your company before applying.

When it comes to sole proprietorships, there are several circumstances where you would need a new EIN. First, if you inherit or buy a business and plan to continue operating the business as a sole proprietorship, you would need a new number. Second, if you change the sole proprietorship to another business structure such as a limited liability company, you will need a new tax identification number. Sole proprietorships do not need a new EIN when moving to a new location, expanding, or changing their name with the same owner.

Corporations need a new EIN under the following circumstances:

  • Altering the corporate structure.
  • Becoming another corporation's subsidiary.
  • Forming a new corporation by merging with another company.

In these scenarios, corporations do not need to apply for a new ID number:

  • A merger occurs, but the corporation is not affected by the merger and continues normal operations.
  • Bankruptcy filings.
  • Changing the location or name of the company.
  • Transitioning to a tax-exempt entity.
  • Reorganizing but leaving the structure intact.

LLCs are a unique type of business entity and are formed at the state level. These companies do not have a formal IRS tax classification, and the IRS treats them as disregarded entities, partnerships, or sole proprietorships. Single-member LLCs, which are companies owned by one person, must follow the same rules as sole proprietorships, including when it comes to obtaining EINs. If an LLC has employees, for instance, it will need a tax ID.

Like every business entity, there are circumstances when an LLC needs a new ID:

  • Converting from a single-member LLC to a multi-member LLC.
  • The owner(s) of the LLC decide to have the company taxed as a corporation.
  • An owner with previous tax debt incorporates a new LLC.

If your business is a partnership, you need a new identification number if you form a new partnership, transition to a sole proprietorship, or incorporate your business.

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