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Foreign registration worksheets · Illinois

3 Best Foreign Registration Services in Illinois (2026): Worked Prices

Illinois, 2026, foreign registration services: the ranking by value reads Mainstay Filing ($199), Illinois Registered Agent.co ($199) and IL Registered Agent.org ($199). The state's $150 is common to all rows. What differs is the service total, $397 to $497 over three years.
Worked by the Formation Math editorial team

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

The working so far

State fee to register $150 ilsos.gov (checked October 2026) as the source
One-year range $199 Provider charges only
Totals after three years $397 to $497 Opening price and two renewals
What the state collects by year 3 $300 The same whoever registers
First crossover No break-even No change in order

Rows ranked by value

Ranked by score; every price comes from a company page. The $150 state fee is left out of the rows.

1
Top score

1. Mainstay Filing: best for repeat registrations

$199 for registration, $149 for the agent after that
Year-1 price $199
Price after year 1 $149/yr
Sum of 3 years $497

Mainstay Filing comes out on top. Working: $199 over Illinois's own fee, followed by $149 a year for the agent.

The $100 three-year premium over Illinois Registered Agent.co buys coverage, and coverage decides this ranking.

From year two: $149 per year for the agent, everywhere.

The price buys

  • The foreign registration filing
  • Registered agent with no charge in year one
  • A price that does not change by state

Adds up

  • The first agent year is covered
  • Covers all fifty states
  • $199 above the state fee

Does not add up

  • $50 above Illinois Registered Agent.co at renewal
2
Built for Illinois

2. Illinois Registered Agent.co: best for adding exactly one state

$199 for registration, $99 for the agent after that
Year-1 price $199
Price after year 1 $99/yr
Sum of 3 years $397

Illinois Registered Agent.co scores second. Working: $199 beyond the state fee, year-one agent included, then $99 a year.

The price buys

  • Filing delivered to the state
  • Year-one agent service

Adds up

  • Then $99 a year
  • Agent included to start
  • Service fee of $199

Does not add up

  • A second provider is needed at home
3
Built for Illinois

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

$199 for registration, $99 for the agent after that
Year-1 price $199
Price after year 1 $99/yr
Sum of 3 years $397

IL Registered Agent.org scores third. Working: $199 beyond the state fee, year-one agent included, then $99 a year.

No difference in price from Illinois Registered Agent.co.

The price buys

  • Filing delivered to the state
  • Year-one agent service

Adds up

  • Then $99 a year
  • Service fee of $199
  • Agent included to start

Does not add up

  • A second provider is needed at home

What each row adds up to

No. Provider Year 1 total Total at year 2 Total at year 3 Total at year 5
1 Mainstay Filing $199 $348 $497 $795 Visit Mainstay Filing Partner link. We may earn money if you buy.
2 Illinois Registered Agent.co $199 $298 $397 $595 Visit Illinois Registered Agent.co Partner link. We may earn money if you buy.
3 IL Registered Agent.org $199 $298 $397 $595 Visit IL Registered Agent.org Partner link. We may earn money if you buy.

Prices as published on November 13, 2026; year one, then renewals added one at a time. No row passes another within ten years.

Do the sum

Change the years to redo the addition.

After 3 years, the totals are Mainstay Filing $497, Illinois Registered Agent.co $397, IL Registered Agent.org $397. Lowest total at that point: Illinois Registered Agent.co.

Illinois state fees (official)

Term Value Where it comes from
Filing the registration $150 ilsos.gov (checked October 2026) as the source
Annual report $75 ilga.gov (checked October 2026) as the source
Sum of state fees, years 1 to 3 $300 Adds the rows above

To get the three-year state figure, add the filing fee, the reports due in years two and three, and any yearly minimum tax. Costs with no fixed amount, such as newspaper publication, are mentioned but not added.

What settled the order

Mainstay Filing wins items covered per dollar, worth 28%, with Illinois Registered Agent.co close behind.

Several states at one price beat Illinois Registered Agent.co's lower renewal.

Illinois foreign LLC registration fee and rules, from the source

The Illinois Secretary of State, Department of Business Services, Limited Liability Division collects $150 and the Application for Admission to Transact Business (Form LLC-45.5) from out-of-state LLCs doing business in Illinois. It requires certificate of Good Standing or Existence dated inside 60 days.

What skipping it can cost: no standing as plaintiff (805 ILCS 180/45-45(a)); back fees on top.

Official wording: ilga.gov (checked October 2026) as the source

The no-service row

Cost of filing yourself: $300 to the state over three years. Service totals of $397 to $497 are the price of avoiding the forms.

About these figures

How much does Illinois take to register an out-of-state LLC?

$150 in state fees, with $199 more if you hire a service.

What do the services add up to over three years?

Between $397 to $497 for three years of service.

Which form does the registering?

The form is Application for Admission to Transact Business (Form LLC-45.5), and the Illinois Secretary of State, Department of Business Services, Limited Liability Division receives it.

Does Illinois ask for a paper from the home state?

Yes, and it must be under 60 days old: certificate of Good Standing or Existence.

What recurring filing comes after registration?

The annual report, which costs $75.

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

No break-even inside ten years.

Which foreign registration service is best value in Illinois?

Mainstay Filing takes the first row, Illinois Registered Agent.co the second, IL Registered Agent.org the third.

Keep working

Foreign registration worksheets, all 50 states Best foreign registration services overall The method

Inputs and sources

  1. Illinois Secretary of State, Department, per ilsos.gov, August 2026.
  2. Illinois Secretary of State, Department, per ilsos.gov, August 2026.
  3. 805 ILCS 180/5-5, per ilga.gov, August 2026.
  4. Illinois formation fee: Filing fee, per ilga.gov, October 2026.
  5. Illinois formation fee: Filing fee, per ilsos.gov, October 2026.
  6. Illinois registered agent statute, per ilga.gov, October 2026.
  7. Form LLC-45.5, Application for Admission, per ilsos.gov, October 2026.
  8. Form LLC-45.40, Application for Withdrawal, per ilsos.gov, October 2026.
  9. 805 ILCS 180/45-45, consequences of, per ilga.gov, October 2026.
  10. 805 ILCS 180/45-47, activities that, per ilga.gov, October 2026.
  11. 805 ILCS 180/45-45, per ilga.gov, November 2026.
  12. Prices from Mainstay Filing, Illinois service page, November 13, 2026
  13. Prices from Illinois Registered Agent.co, pricing page, November 13, 2026
  14. Prices from IL Registered Agent.org, pricing page, November 13, 2026