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Founder Mentor Guide

Mentor notes 1 · Illinois

Illinois LLC Formation Walkthrough (2026): 7 Stages and the 3 Best LLC Services

Here is the short answer for forming an LLC in Illinois in 2026: IL Registered Agent.org ($199), Illinois Registered Agent.co ($199) and Mainstay Filing ($199), ranked from first to last. Expect 7 stages and a $150 state fee, then $75 for the Limited Liability Company Annual Report.

Advice from the Founder Mentor Guide mentors

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Cost to form
$150
We pulled this from ilsos.gov in October 2026
Limited Liability Company Annual Report
$75 a year
Official timing, quoted: before the first day of the entity's anniversary month
Three years of state fees
$300
State charges only
Stages
7
Each one explained

Walkthrough goals

  • The Illinois formation paper, its price and who gets it
  • What the agent rule says
  • Upkeep that repeats
  • Which services we recommend and why

Our shortlist for Illinois

Five weighted criteria set the order (see how we score), and three-year cost and work taken off your desk count most.

Our call

1. IL Registered Agent.org: best for Illinois LLCs working to a budget

Top recommendation$199 in year one, $99 after

In Illinois, IL Registered Agent.org leads the list: the formation costs $199, and each later year of agent service is $99.

Cost settles it: three years here come to less than at Mainstay Filing.

The Limited Liability Company Annual Report is not in the price, so you file it every year.

What you get

  • Filing made with the state
  • A year of agent service comes with the price

What works

  • No agent fee in year one
  • $199 plus the state fee
  • The agent renews at $99

What to watch

  • Preparing the Limited Liability Company Annual Report is on your plate
  • An EIN add-on costs $99
Visit IL Registered Agent.orgPartner link. We may earn money if you buy.

Our call

2. Illinois Registered Agent.co: best for a local filer

Illinois specialist$199 in year one, $99 after

Pick number 2 is Illinois Registered Agent.co, where the formation costs $199, and each later year of agent service is $99.

The Limited Liability Company Annual Report is not in the price, so you file it every year.

It charges exactly what IL Registered Agent.org charges.

What you get

  • Filing made with the state
  • A year of agent service comes with the price

What works

  • $199 plus the state fee
  • The agent renews at $99
  • No agent fee in year one

What to watch

  • Preparing the Limited Liability Company Annual Report is on your plate
  • An EIN add-on costs $99
Visit Illinois Registered Agent.coPartner link. We may earn money if you buy.

Our call

3. Mainstay Filing: best for one bill for filing and upkeep

Works in every stateYear one $199; renewal $199; state fee separate

Pick number 3 is Mainstay Filing, where it wraps the filing, your registered agent and the annual report into $199 a year, and the renewal does not budge from $199.

Across three years it trails IL Registered Agent.org by $200.

It files every Limited Liability Company Annual Report for you; the only extra is the state's own $75.

What you get

  • Formation paperwork handled
  • Registered agent all year long
  • Annual report filed for you
  • The EIN application comes with it
  • No markup on the state fee

What works

  • $199 when you renew
  • The EIN application is covered
  • $199 a year for filing, agent and report

What to watch

  • A yearly premium of $100 over IL Registered Agent.org
Visit Mainstay FilingPartner link. We may earn money if you buy.

Scores and prices together

#ServiceFirst yearFrom year twoThree-year total
1IL Registered Agent.org$199$99/yr$397Visit IL Registered Agent.orgPartner link. We may earn money if you buy.
2Illinois Registered Agent.co$199$99/yr$397Visit Illinois Registered Agent.coPartner link. We may earn money if you buy.
3Mainstay Filing$199$199/yr$597Visit Mainstay FilingPartner link. We may earn money if you buy.
Listed prices, viewed November 13, 2026. No row folds in the $150 state fee.

How a Illinois LLC gets formed

  1. Stage 1

    Confirm nobody else owns the name

    Look your name up on the Illinois register at the Illinois Secretary of State. It takes a few minutes and spares you a rejected filing.

    A spare name saves you a second search.

  2. Stage 2

    Line up a registered agent

    Every LLC must name a registered agent with an in-state street address. An Illinois resident, or a business authorized to do business in Illinois. The LLC cannot act as its own agent.

    The address has to be a registered office in Illinois that matches the agent's business office. A P.O. box alone is not accepted.

    Any of the services we phone can be your registered agent.

    Check it yourself: We pulled this from ilga.gov in October 2026

  3. Stage 3

    Decide whether to do it yourself

    The state takes $150 regardless. If you hire a service from our list, add $199.

  4. Stage 4

    The paper to file is the Articles of Organization

    The Articles of Organization (Form LLC-5.5) is the key document. It goes to the Illinois Secretary of State, the fee is $150, and the rule sits in 805 ILCS 180/5-5.

    Check it yourself: We pulled this from ilsos.gov in October 2026

  5. Stage 5

    Apply for an Employer Identification Number

    With approval in your hands, request an EIN so the LLC can open accounts under its own name. Mainstay Filing prepares the EIN application inside its package.

  6. Stage 6

    Document how the company runs

    Even if you are the only owner of a Illinois LLC, write one anyway and file it with your records.

  7. Stage 7

    Stay in good standing in Illinois

    The filing that returns on schedule is the Limited Liability Company Annual Report ($75, every year, by before the first day of the entity's anniversary month). A late one carries $100.

    Check it yourself: We pulled this from ilsos.gov in October 2026

The bill

EntryGoes toTotal
Formation feeState office$150
Limited Liability Company Annual ReportState office$75 every year
Missing the deadlineState office$100
Service fees (optional)The service$199 in year one
What the state collects by year threeState office$300
The state's fees come from official pages, listed below. Over three years they add up to the filing, two reports and, in a few states, a minimum tax.

How we scored the Illinois picks

edged out on three-year bill, which counts for 32%.

IL Registered Agent.org costs $397 across three years, saving you $200 compared with Mainstay Filing.

Illinois questions answered

What does Illinois charge to form an LLC?

$150, paid to the state. Paying a service raises the first-year bill by $199.

Which form creates the LLC?

Mail or upload the Articles of Organization (Form LLC-5.5) to the Illinois Secretary of State.

Is a registered agent required?

Every LLC must name a registered agent with an in-state street address.

What does Illinois require each year?

Send in the Limited Liability Company Annual Report every year; it costs $75 and the deadline is before the first day of the entity's anniversary month.

Can I form the LLC without a service?

Nothing stops you. Illinois wants $150, and the LLC has to name a registered agent, which you can be or hire.

Which LLC service should a first-time founder use?

Go with IL Registered Agent.org: $199 to get going, agent service for year one included, then $99 each year. Then Illinois Registered Agent.co and Mainstay Filing.

Where we got the facts

  1. Our Illinois Secretary of State, Department of Business Services notes lean on ilsos.gov as of August 2026.
  2. Our Illinois Secretary of State, Department of Business Services notes lean on ilsos.gov as of August 2026.
  3. Our 805 ILCS 180/5-5 notes lean on ilga.gov as of August 2026.
  4. Our Illinois formation fee: Filing fee, official source notes lean on ilga.gov as of October 2026.
  5. Our Illinois formation fee: Filing fee, official source notes lean on ilsos.gov as of October 2026.
  6. Our Illinois registered agent statute notes lean on ilga.gov as of October 2026.
  7. IL Registered Agent.org: pricing page, opened November 13, 2026
  8. Illinois Registered Agent.co: pricing page, opened November 13, 2026
  9. Mainstay Filing: Illinois service page, opened November 13, 2026