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Biz Formation Report

Rankings of registered agents, LLC formation and foreign registration services in all 50 states.

LLC formation report · Illinois

3 Best LLC Services in Illinois (2026)

By the Biz Formation Report editorial team

Biz Formation Report ranks LLC services in Illinois for 2026 as IL Registered Agent.org ($199), Illinois Registered Agent.co ($199) and Mainstay Filing ($199), in that order. IL Registered Agent.org earns the top grade: forming in Illinois costs $199 beyond the state's fee, with the first agent year included, and keeping the agent runs $99 a year.

No.1

Top pick on this page

1. IL Registered Agent.org: best for an Illinois LLC that expects to stay put

Score9.4out of 10
$199 for formation, then $99 a year for the agent, plus the state fee

Top grade, IL Registered Agent.org: $199 for formation on top of the state fee, then $99 a year for the agent.

The plan seats the company at an in-state street address and posts scans of papers served there to your online account.

The Limited Liability Company Annual Report is outside its published prices, so you submit it to Illinois yourself every year.

Three years of service cost less here than with Mainstay Filing, and cost counts heavily in the grade.

What you get

  • LLC filing done for you
  • The first year as your registered agent

Good

  • Formation costs $199 before the state fee
  • The first year as your registered agent is included
  • Agent renewal of $99

Weak spots

  • Does not handle the Limited Liability Company Annual Report
  • The EIN application costs $99 extra
Visit IL Registered Agent.orgPartner link. We may earn money if you buy.
Read the IL Registered Agent.org review
No.2

Best local option

2. Illinois Registered Agent.co: best for local Illinois formation

Score9.2out of 10
$199 for formation, then $99 a year for the agent, plus the state fee

Second grade, Illinois Registered Agent.co: $199 for formation on top of the state fee, then $99 a year for the agent.

The plan seats the company at an in-state street address and posts scans of papers served there to your online account.

The Limited Liability Company Annual Report is outside its published prices, so you submit it to Illinois yourself every year.

IL Registered Agent.org and Illinois Registered Agent.co publish the same prices and plan features, so the grades are close and either is a sound pick.

What you get

  • LLC filing done for you
  • The first year as your registered agent

Good

  • $99 a year for the agent from year two
  • The first year as your registered agent is included
  • A $199 formation price, state fee extra

Weak spots

  • Does not handle the Limited Liability Company Annual Report
  • The EIN application costs $99 extra
Visit Illinois Registered Agent.coPartner link. We may earn money if you buy.
Read the Illinois Registered Agent.co review
No.3

All-in price

3. Mainstay Filing: best for formation, agent and annual report on one invoice

Score9.1out of 10
$199 a year plus the state fee, $349 due at checkout

Third grade, Mainstay Filing: a flat $199 yearly fee takes in the Illinois formation, your registered agent and the annual report.

The renewal covers the Limited Liability Company Annual Report, which Mainstay files for you. Illinois collects $75 every year, with a deadline of before the first day of the entity's anniversary month, and a late filing adds $100; Mainstay passes the state's fee through at cost.

IL Registered Agent.org is $200 cheaper across three years, and that difference lowers Mainstay Filing's cost grade.

What you get

  • Formation paperwork handled and filed
  • A registered agent for the whole year
  • The annual report prepared and filed
  • The EIN application

Good

  • Renewal is $199 with no add-ons
  • A single $199 yearly price, including the annual report
  • Includes the EIN application
  • Illinois's state fee is passed through at cost

Weak spots

  • Its agent renews at $100 a year more than IL Registered Agent.org's
Visit Mainstay FilingPartner link. We may earn money if you buy.
Read the Mainstay Filing review

Summary of the 3 grades

RankProviderGradeService feeYear twoBest fitSite
1IL Registered Agent.org9.4$199$99/yrAn Illinois-only LLC keeping costs downVisit IL Registered Agent.orgPartner link. We may earn money if you buy.
2Illinois Registered Agent.co9.2$199$99/yrAn Illinois-only LLC keeping costs downVisit Illinois Registered Agent.coPartner link. We may earn money if you buy.
3Mainstay Filing9.1$199$199/yrFormation, agent and annual report on one invoiceVisit Mainstay FilingPartner link. We may earn money if you buy.

The grades are editorial: Biz Formation Report assigns every mark out of 10 using the criteria on How we rank, not customer ratings.

Illinois LLC service prices, 2026: year one, renewal and three-year outlay

ProviderYear 1Year 2Year 3Three-year outlayLimited Liability Company Annual Report done for you
IL Registered Agent.org$199$99$99$397No
Illinois Registered Agent.co$199$99$99$397No
Mainstay Filing$199$199$199$597Yes

All prices were taken from the companies' own websites on November 12, 2026. Illinois's $150 filing fee is payable on top of each row and is not part of these totals.

The basis for the order

Of the grade, 32% rests on three-year bill and 32% on what the money buys; renewal handling, local rules match and pricing openness share the remaining 36%. Three-year bill decided Illinois.

Total outlay with IL Registered Agent.org over three years: $397, $200 less than Mainstay Filing. Mainstay would add the Limited Liability Company Annual Report filing, but owners can file it alone for the state fee, so the lower price decided the grade.

Every criterion and weight is listed on How we rank.

Illinois LLC filing fee and form, from official sources

The Illinois Secretary of State charges $150 for the Articles of Organization (Form LLC-5.5). Each provider here adds that fee at cost on top of its own.

What a Illinois LLC owes after formation

Expect the Limited Liability Company Annual Report every year, with a deadline of before the first day of the entity's anniversary month. It costs $75. Late filing adds $100. Every LLC must name a registered agent with an in-state street address.

Illinois LLC service: common questions

What does Illinois charge to start an LLC, all in?

$150 goes to the state and $199 to the service.

Which document starts the LLC?

the Illinois Secretary of State accepts the Articles of Organization (Form LLC-5.5).

Is a registered agent mandatory for an Illinois LLC?

Yes. Illinois requires one, with a physical street address in the state, from the day the LLC exists.

What recurring paperwork follows an LLC in Illinois?

A single item: the Limited Liability Company Annual Report, filed every year (before the first day of the entity's anniversary month) for $75.

Does the service price cover the EIN?

The Mainstay Filing yearly price covers it. IL Registered Agent.org and Illinois Registered Agent.co list it at $99. The IRS does not charge for issuing an EIN.

What is the best LLC service in Illinois, by our report?

IL Registered Agent.org: $199 plus the Illinois filing fee, year-one registered agent service included, then $99 a year.

Read next

Source notes

  1. Illinois Secretary of State, Department of Business Services, Limited Liability Division (verified August 2026)
  2. Illinois Secretary of State, Department of Business Services, Limited Liability Division (verified August 2026)
  3. 805 ILCS 180/5-5 (verified August 2026)
  4. Illinois formation fee: Filing fee, official source (verified October 2026)
  5. Illinois formation fee: Filing fee, official source (verified October 2026)
  6. Illinois registered agent statute (verified October 2026)
  7. Pulled November 12, 2026: IL Registered Agent.org, pricing and service pages
  8. Pulled November 12, 2026: Illinois Registered Agent.co, pricing and service pages
  9. Pulled November 12, 2026: Mainstay Filing, Illinois service page