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LLC formation worksheets · Illinois

3 Best LLC Services in Illinois (2026): Worked Prices

Worked out for 2026, the best-value LLC formation services in Illinois come to Illinois Registered Agent.co ($199), IL Registered Agent.org ($199) and Mainstay Filing ($199), in that order. The service rows total $397 to $597 over three years; Illinois separately charges $150 to file, whoever does it.
Worked by the Formation Math editorial team

↓ Sorted by: Cost first (42%), items covered second (28%), three smaller checks after. See the working

Illinois: the numbers worked

Filing charge $150 ilsos.gov (checked October 2026) as the source
Year-one totals $199 Before government fees
Totals after three years $397 to $597 First year + 2 renewals
State fees, summed over 3 years $300 Left out of the score
Where rows cross Not within ten years Rows keep their positions through year 10

Rows ranked by value

Rows are sorted by the method. None of the rows includes the $150 state fee.

1
Row one

1. Illinois Registered Agent.co: best for companies that will stay in one state

$199 plus state fee, then $99 a year
Year-1 price $199
Price after year 1 $99/yr
Sum of 3 years $397

Row one is Illinois Registered Agent.co. The math: $199 to start (agent service for year one included), then $99 each year.

The sums settle it: three years here cost less than three years at Mainstay Filing.

You would still do the Limited Liability Company Annual Report yourself.

The price buys

  • The Illinois formation filing
  • Year-one agent service

Adds up

  • Starts at $199
  • First agent year included
  • $99 a year afterward

Does not add up

  • Filing the Limited Liability Company Annual Report is left to you
  • EIN application costs $99 more
2
Illinois only

2. IL Registered Agent.org: best for a small agent renewal

$199 plus state fee, then $99 a year
Year-1 price $199
Price after year 1 $99/yr
Sum of 3 years $397

Next in the working, IL Registered Agent.org: $199 to start (agent service for year one included), then $99 each year.

You would still do the Limited Liability Company Annual Report yourself.

Year one and renewal both match Illinois Registered Agent.co.

The price buys

  • The Illinois formation filing
  • Year-one agent service

Adds up

  • $99 a year afterward
  • Starts at $199
  • First agent year included

Does not add up

  • Filing the Limited Liability Company Annual Report is left to you
  • EIN application costs $99 more
3
Any state

3. Mainstay Filing: best for paying once for filing and upkeep

Year 1: $199. Renewal: $199. State fee: separate.
Year-1 price $199
Price after year 1 $199/yr
Sum of 3 years $597

Row 3 belongs to Mainstay Filing because $199 a year pays for the filing, the registered agent and the annual report, so year two is $199 again.

Three years cost $200 more here than at Illinois Registered Agent.co, and cost carries 42% of the score.

Each Limited Liability Company Annual Report is part of the service, with the state's $75 billed at cost.

The price buys

  • Filing delivered to the state
  • Registered agent, covered all year
  • Annual report, filed when due
  • EIN application, handled
  • State fee charged at cost

Adds up

  • EIN application is part of the price
  • $199 a year includes filing and agent and report
  • Renewal stays at $199

Does not add up

  • Renewal is $100 higher than Illinois Registered Agent.co's

Cumulative cost, year by year

No. Provider Year 1 total Total at year 2 Total at year 3 Total at year 5
1 Illinois Registered Agent.co $199 $298 $397 $595 Visit Illinois Registered Agent.co Partner link. We may earn money if you buy.
2 IL Registered Agent.org $199 $298 $397 $595 Visit IL Registered Agent.org Partner link. We may earn money if you buy.
3 Mainstay Filing $199 $398 $597 $995 Visit Mainstay Filing Partner link. We may earn money if you buy.

Year one plus renewals, from the prices read on November 13, 2026. No break-even shows up in ten years.

Do the sum

The calculator adds year one and the renewals for every row once you choose the years, and counts the EIN application if ticked.

3 years of fees add to Illinois Registered Agent.co $397, IL Registered Agent.org $397, Mainstay Filing $597. Row with the smallest sum: Illinois Registered Agent.co.

State fees with citations

Term Value Where it comes from
Filing the articles $150 ilsos.gov (checked October 2026) as the source
Limited Liability Company Annual Report $75 every year ilsos.gov (checked October 2026) as the source
Penalty if the report is late $100 ilsos.gov (checked October 2026) as the source
State fees added over 3 years $300 Adds the rows above

Each state row cites its official source. The 3-year total adds the filing, the year-2 and year-3 reports and any minimum tax.

Notes on the order

Three-year total put Illinois Registered Agent.co in row one. That term is 42% of the score; items covered per dollar, year-two change, crossover year and published detail make up the rest.

Three years with Illinois Registered Agent.co: $397; the same three years at Mainstay Filing cost $200 more.

If you need the EIN application, the rows cross in year 2, as Mainstay Filing passes Illinois Registered Agent.co.

Illinois LLC filing fee and rules, from the source

The Articles of Organization (Form LLC-5.5) and $150 go to the Illinois Secretary of State, under 805 ILCS 180/5-5. Every LLC must name a registered agent with an in-state street address.

Cited at: ilsos.gov (checked October 2026) as the source

Filing it yourself, worked out

Skip the service and Illinois still collects $300 across three years while you handle every form. The services charge $397 to $597 for that work.

Common questions

What does an LLC formation service cost in Illinois?

$199 for year one across our rows, plus the state's $150 fee.

What do the services add up to over three years?

Year one plus two renewals gives $397 to $597.

What is the Illinois fee to file an LLC?

$150; you submit the Articles of Organization (Form LLC-5.5).

What does Illinois collect each year after formation?

Illinois expects the Limited Liability Company Annual Report every year at $75, before the first day of the entity's anniversary month.

Does the price include the EIN application?

$99 extra at Illinois Registered Agent.co, $99 extra at IL Registered Agent.org and it comes with Mainstay Filing.

In what year does one service pass another in total cost?

No break-even inside ten years.

Which LLC formation service is best value in Illinois?

Illinois Registered Agent.co, which wins on three-year total. Then IL Registered Agent.org and Mainstay Filing.

See also

LLC formation worksheets, all 50 states Best LLC services overall The method

Inputs and sources

  1. Check Illinois Secretary of State, Department at ilsos.gov; last read August 2026.
  2. Check Illinois Secretary of State, Department at ilsos.gov; last read August 2026.
  3. Check 805 ILCS 180/5-5 at ilga.gov; last read August 2026.
  4. Check Illinois formation fee: Filing fee at ilga.gov; last read October 2026.
  5. Check Illinois formation fee: Filing fee at ilsos.gov; last read October 2026.
  6. Check Illinois registered agent statute at ilga.gov; last read October 2026.
  7. The Illinois Registered Agent.co pricing page supplied the prices on November 13, 2026
  8. The IL Registered Agent.org pricing page supplied the prices on November 13, 2026
  9. The Mainstay Filing Illinois service page supplied the prices on November 13, 2026