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Formation Scorecard

Foreign registration scorecard · Illinois

3 Best Foreign Registration Services in Illinois (2026)

On the Formation Scorecard 2026 scorecard for foreign registration services in Illinois the order reads Mainstay Filing ($199), IL Registered Agent.org ($199) and Illinois Registered Agent.co ($199). Mainstay Filing posts the top score: $199 on top of the state's fee, with a free first year as your registered agent and the same price in every state.
Researched and written by the Formation Scorecard editorial team
Rank #1 Top pick on this page

1. Mainstay Filing: best for companies spread across states

9.4 Editor score out of 10
$199 service fee, $349 due at checkout including the state fee; agent $149 yearly from year two

Mainstay Filing leads the card: it files the Illinois registration for $199 and acts as your registered agent, free for year one and $149 a year after.

The agent is free in year one and $149 a year after that, wherever the company registers.

Mainstay's three-year total sits $100 above IL Registered Agent.org's, which the extra coverage earns back in our scoring.

What you get

  • Registration prepared and submitted
  • The first registered agent year at no charge
  • Legal papers served on the company scanned free on the same business day

Strengths

  • Served papers scanned on the day they arrive, free
  • $199 service fee, with the state fee on top
  • Same price across all fifty states
  • Registered agent free for year one

Watch for

  • Agent renewal of $149 is $50 more than IL Registered Agent.org charges
Visit Mainstay FilingPartner link. We may earn money if you buy. Mainstay Filing: the full write-up
Rank #2 Lower renewal than Mainstay

2. IL Registered Agent.org: best for companies that add just Illinois

8.9 Editor score out of 10
Service fee $199 with the state fee added; agent renewing at $99

IL Registered Agent.org takes second spot: $199 beyond the state fee to register in Illinois, agent renewing at $99.

The plan puts the company at an in-state street address and scans papers served on it to your online account.

What you get

  • Illinois registration filed for you
  • Year-one registered agent service included

Strengths

  • A $199 service fee before the state's
  • $99 per year for the agent after the first
  • Includes the first registered agent year

Watch for

  • Limited to Illinois; your home state still needs an agent
  • $99 extra for the EIN application
Visit IL Registered Agent.orgPartner link. We may earn money if you buy. IL Registered Agent.org: the full write-up
Rank #3 Lower renewal than Mainstay

3. Illinois Registered Agent.co: best for registrations in Illinois only

8.7 Editor score out of 10
Service fee $199 with the state fee added; agent renewing at $99

Illinois Registered Agent.co takes third spot: $199 beyond the state fee to register in Illinois, agent renewing at $99.

The plan puts the company at an in-state street address and scans papers served on it to your online account.

Illinois Registered Agent.co mirrors IL Registered Agent.org on price and plan features, so little divides them.

What you get

  • Illinois registration filed for you
  • First-year registered agent service

Strengths

  • Then $99 a year to keep the agent
  • Registered agent service for year one is in the price
  • $199 service fee plus the registration fee

Watch for

  • Limited to Illinois; your home state still needs an agent
  • $99 extra for the EIN application
Visit Illinois Registered Agent.coPartner link. We may earn money if you buy. Illinois Registered Agent.co: the full write-up

The 3 entries on one card

Place Service Card score Service fee Year two Best for Go
1 Mainstay Filing 9.4 $199 $149/yr Companies spread over several states Visit Mainstay FilingPartner link. We may earn money if you buy.
2 IL Registered Agent.org 8.9 $199 $99/yr The lowest agent renewal we rank here Visit IL Registered Agent.orgPartner link. We may earn money if you buy.
3 Illinois Registered Agent.co 8.7 $199 $99/yr The lowest agent renewal we rank here Visit Illinois Registered Agent.coPartner link. We may earn money if you buy.

Formation Scorecard assigns each mark out of 10 itself, using the weighted criteria on How we rank. No customer ratings feed in.

Illinois foreign registration service cost in 2026: first year, renewal and the three-year tally

Service First year Second year Third year Three-year tally Agent paid in year one
Mainstay Filing $199 $149 $149 $497 Free
IL Registered Agent.org $199 $99 $99 $397 Included
Illinois Registered Agent.co $199 $99 $99 $397 Included

Each price comes from the company's own site, read on November 12, 2026. Add Illinois's $150 registration fee to each row; the tally above leaves it out.

What broke the tie

Coverage of the price decided the Illinois card. The method puts 25% on cost across three years and 25% on coverage of the price, then shares 50% among renewal terms, state-by-state fit and pricing clarity.

A foreign registration touches two states, so a single provider at one price in both earned the most coverage points, ahead of IL Registered Agent.org.

Every criterion and weight appears on How we rank.

Foreign LLC registration in Illinois: fee, form and filing office

An outside company registers by sending the Application for Admission to Transact Business (Form LLC-45.5) to the Illinois Secretary of State, Department of Business Services, Limited Liability Division, with a $150 state fee. Illinois additionally requires certificate of Good Standing or Existence, dated no more than 60 days before filing.

Once registered, the company files the annual report ($75), due within the 60 days before your anniversary month.

Gather these before filing

  • Certificate of Good Standing or Existence, issued no earlier than 60 days before filing.
  • The company name exactly as the home state has it, plus the date it was formed.
  • An in-state registered agent; any service on this card can fill that role.
  • The state fee of $150, sent in with the filing.
  • A calendar date for the annual report and its $75 fee.

The price of ignoring Illinois registration

An unregistered outside LLC cannot sue in Illinois courts until it registers (805 ILCS 180/45-45(a)). Its contracts remain valid (805 ILCS 180/45-45(b)). Fees for the unregistered period come due as well.

Illinois foreign registration service: quick questions

Does Illinois make an outside LLC register before operating?

Yes, when the company does business there. Until it registers, the state's courts are closed to its lawsuits.

What will foreign registration run in Illinois?

Expect $150 for the state plus $199 for the service.

What is the registration form called in Illinois?

The form goes to the Illinois Secretary of State, Department of Business Services, Limited Liability Division; its exact name is in the facts above.

Is a home-state certificate part of the Illinois filing?

Yes, the state wants certificate of Good Standing or Existence, no older than 60 days.

Does a registered company still need a registered agent?

Yes, a registered agent with an in-state street address has to stay on file.

Which foreign registration service leads the card for Illinois?

Mainstay Filing, since $199 plus state fees in any state, year-one registered agent service included.

More from us

Where the figures come from

  1. Illinois Secretary of State, Department of Business Services, Limited Liability Division, as of August 2026
  2. Illinois Secretary of State, Department of Business Services, Limited Liability Division, as of August 2026
  3. 805 ILCS 180/5-5, as of August 2026
  4. Illinois formation fee: Filing fee, official source, as of October 2026
  5. Illinois formation fee: Filing fee, official source, as of October 2026
  6. Illinois registered agent statute, as of October 2026
  7. Form LLC-45.5, Application for Admission, as of October 2026
  8. Form LLC-45.40, Application for Withdrawal, as of October 2026
  9. 805 ILCS 180/45-45, consequences of transacting business without admission, as of October 2026
  10. 805 ILCS 180/45-47, activities that are not transacting business, as of October 2026
  11. 805 ILCS 180/45-45, as of November 2026
  12. Read on November 12, 2026: Illinois service page for Mainstay Filing
  13. Read on November 12, 2026: pricing and service pages for IL Registered Agent.org
  14. Read on November 12, 2026: pricing and service pages for Illinois Registered Agent.co