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Search Your Business Name With the Illinois Secretary of State and Register Your LLC

Whether you’re searching for the right Illinois business name or registering your LLC with the IL Secretary of State, we can help. We’ve got all the information you need on the Illinois business entity search, LLC naming rules, fictitious names and registering your business.

Illinois Business Name Lookup

You need to check whether there’s already another Illinois LLC registered with your desired business name. That means searching the Illinois Secretary of State website using their “Corporation/LLC Database.” We make that search easy with our business name search tool. Just enter your details and we’ll look up LLCs and corporations in Illinois to check your name isn’t already in use.

If the business name is already used, that means it’s not available and you won’t be able to register it. Try searching for a different business name instead. You can also search for the name directly on the IL Secretary of State website.

Illinois Secretary of State business namesearch tool

Illinois SOS Rules for LLC Business Names

Once you’ve decided on a name for your LLC and checked business name availability, you’ll need to meet Illinois Secretary of State naming rules. These do vary from state to state — we’ve got general naming rules below, as well as naming rules specific to LLC businesses formed in IL.

Standard LLC Naming Rules

These rules typically apply to all LLCs, no matter what state they are formed in. You will need to pay attention to these rules as they will influence the name you choose for your Illinois LLC.

Your LLC Business Name Must Be Unique

The business name you have chosen cannot be used by any other LLC or corporation in the state of Illinois. This is why you should check business name availability on the IL SOS website.

Your LLC Business Name Must Not Be Confusable With Another Business Name

It’s not enough for your IL LLC name to be unique. It also cannot be similar to the name of a corporation or LLC in Illinois. For example, you cannot use the following factors to say your name is different from the name of another business:

  • Suffixes, such as Corporation, Company, Incorporated, Incorporation, Limited, Corp., Co., Inc., Ltd., LLC, etc.
  • Definite articles like “A,” “And,” “An,” “&,” “The,” etc.
  • The singular, plural or possessive forms of a word
  • Abbreviations, punctuation, symbols, fonts, typefaces, etc.

Your LLC Business Name Must Contain Certain Words

All LLCs must have the words “Limited Liability Company,” “L.L.C.” or “LLC” in their name. These words should normally come at the end of the name.

Your LLC Business Name May Have Other General Restrictions

Most states will not allow you to form LLCs with names that:

  • Are very similar to the name of a federal or IL agency or organization (e.g. FBI, FDA, Illinois Department of Revenue, Illinois Police, Treasury, etc.)
  • Suggest affiliation with a federal or state agency or organization
  • Use the term “Olympic” or any terms that are trademarks of the Olympic organization
  • Imply a purpose that it would be illegal for your business to carry out

Specific LLC Naming Rules for Illinois

In addition to the general rules listed above, the Illinois Secretary of State has some specific business naming rules for your LLC. You will need to follow these rules if you want to name your IL business appropriately.

  • Certain restricted words need additional paperwork if you want to use them in your business name. This includes both names associated with institutions and words associated with certain qualified professions. This list of words includes: Insurance, Surety, Underwriters, Bank, Bankers, Banking, or any licensed professional services.

Read more about Illinois Secretary of State business naming rules.

Illinois LLC Assumed Names

You might choose to do business under a different name from your legal LLC name. In Illinois, doing business under a different name is known as an “Assumed Name.” You might choose to use a different name from your formal LLC name for a variety of reasons.

For example, your LLC might be called Illinois Great Lakes Holding Company LLC, but you have a chain called Lake Illinois Tourism and Leisure. You should file an Adopting an Assumed Name form to let the Illinois Secretary of State know, or you can have Incfile do it on your behalf through our Assumed Business Name service.

Incfile’s Assumed Business Name service

Business Name Registration for Your Illinois LLC

Once you’ve searched for your Illinois business name with our tool to check availability, you’ll need to do a little more legwork. Make sure you’ve followed the naming rules and decided whether you need a fictitious name. After that, you can register your Illinois LLC name. There are a couple of ways to do this.

  • If you don’t want to form your Illinois LLC right now, you can reserve the business name with the Illinois Secretary of State. You will need to complete form LLC-1.15 Application to Reserve a Name and file it with the IL SOS. You do not need to reserve a name if you are forming your business right away.
    Illinois SOS LLC name reservation form
  • If you’re ready to start your Illinois LLC, you can file your Articles of Organization with the Illinois Secretary of State, or let Incfile take care of it for you.

FAQs on Naming Your Illinois LLC

You might find the following answers useful.

How Do I Search for My Illinois LLC Business Name?

Just use our business name search tool and enter your proposed business name. We’ll search the register of the Illinois Secretary of State, and let you know if there are any IL corporations or LLCs with that name.

Incfile guide to choosing a business name

Get a Street Address for Your Illinois LLC

If you want a street address in Illinois, Incfile provides a convenient and safe virtual mailbox service. Please note that this may not meet the requirements of the Secretary of State for a registered office or registered agent address, but it is an excellent way to securely access your physical mail from anywhere.

The benefits of our virtual Illinois mailbox service include:

  • One address for all correspondence
  • Review mail wherever you are
  • A professional image for your business
  • A low, fixed price regardless of mail volume

Are There Any Rules on Naming My Illinois LLC ?

Yes. Most LLCs will be bound by general rules (applicable to all LLCs) and specific rules (applicable in the state of Illinois). We’ve detailed these rules above.

Can I Do Business Under a Different Name Than My LLC  Name in Illinois?

Yes. Known as “assumed names,” “fictitious names,” “doing business as names” or “trade names,” you can choose to conduct business under a different name.

Can I Reserve a Name for My Illinois LLC ?

Yes. The Illinois Secretary of State allows you to reserve a name if you don’t want to start your business immediately. If you are ready to start your business now, you do not need to reserve a name.

Useful Resources for Naming Your Illinois LLC

You might find these resources helpful.

Trademarks and Service Marks

You must be careful that your Illinois LLC name does not infringe on the trademark or service mark of another business. The easiest way to make sure your proposed business name does not infringe is to carry out a trademark search through Incfile. If it doesn’t infringe, you can even register it as a trademark yourself.

Incfile Trademark Search and Registration service

Find the Perfect Name for Your Illinois LLC

The perfect business name can be elusive. We have a complete guide to choosing the right business name, but basically, you'll want to choose a name that will:

  • Appeal to your customers
  • Be memorable enough to stand out
  • Best represent your product or services
  • Not be used by another business

Incfile guide to choosing a business name

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What are the fees and requirements to form a business in Illinois?

Filing Time and Price

The state charges this amount to file a new business entity. This fee goes directly to the Secretary of State.

State Fee State Filing Time Expedited Filing Time
$154 2 Weeks 1 Business Day

Compliance Requirements

This report is mandatory and must be filed within the specified time frame in order for the entity to remain in good standing with the state. Failure to file this report can lead to the company being revoked or administratively dissolved.

Annual Report

Frequency: Annually

Due Date: Within 60 days immediately preceding first day of anniversary month.

Filing Fee: $78

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