3 Best Foreign Registration Services in Illinois (2026): Prices Tracked
After this 2026 price pass on Illinois foreign registration services, the order is IL Registered Agent.org ($199), Mainstay Filing ($199) and Illinois Registered Agent.co ($199). $150 goes to the state however you file; the service side adds $397 to $497 over three years.
Tracked by the Filing Price Watch editorial team
Ordered by:
Best value first, using our five measures
Prices on the watchlist
What the state charges to register$150ilsos.gov (pulled October 2026, noted here)
What year one costs$199Provider charges only
Three-year spend$397 to $497Opening year and two more
State fees by year three$300Does not vary by provider
Crossover yearNot within ten yearsNo service overtakes another
Illinois: best value first
Services are ordered by value, and every price comes from a company page. The $150 state fee is kept outside the prices.
#Ordered byPrice in year 1Price at renewalThree-year spend
1
First place
1. IL Registered Agent.org: best for adding just one state
Starts at $199; later years $99
Price in year 1$199
Price after year 1$99/yr
Three-year spend$397
In Illinois, IL Registered Agent.org is the best value because $199 on top of the state fee, with the first agent year included, followed by $99 each year.
It costs less over three years than Mainstay Filing, and three-year cost is 37% of the order.
Price covers
Registration sent to the state office
A year of agent service to begin with
Holds up
Agent renews at $99
Agent service free in year one
$199 to register
Weak spots
Illinois only, so the home state needs its own agent
2
Works in every state
2. Mainstay Filing: best for companies still expanding
Starts at $199; later years $149
Price in year 1$199
Price after year 1$149/yr
Three-year spend$497
Mainstay Filing takes spot 2 because registration in Illinois for $199 plus state fees, with the first agent year paid.
A $100 gap to IL Registered Agent.org at year three decides where it sits.
No agent charge in year one; after that it is $149 a year.
Price covers
Registration done for you
Registered agent is free in year one
One fee wherever you register
Holds up
Registered agent is free in year one
$199 on top of the state's fee
Handy if another state follows
Weak spots
IL Registered Agent.org charges $50 less for the agent
3
Local pick
3. Illinois Registered Agent.co: best for another in-state registrant
Starts at $199; later years $99
Price in year 1$199
Price after year 1$99/yr
Three-year spend$397
Spot 3 goes to Illinois Registered Agent.co: $199 on top of the state fee, with the first agent year included, followed by $99 each year.
IL Registered Agent.org lists exactly the same prices.
Price covers
Registration sent to the state office
A year of agent service to begin with
Holds up
$199 to register
Agent service free in year one
Agent renews at $99
Weak spots
Illinois only, so the home state needs its own agent
Each line above links to the state's own page. Summing them gives the three-year state figure, which covers filing, years two and three of reporting and a minimum tax where there is one.
Why this order for Illinois
Tracked three-year cost gave IL Registered Agent.org the lead. It makes up 37% of the order, and filings covered by the price, renewal movement, crossover year and price visibility cover the remainder.
Three years with IL Registered Agent.org come to $397, while Mainstay Filing runs $100 higher over the same stretch.
Illinois foreign LLC registration fee and rules, as written by the state
To register: 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 $150. Send along certificate of Good Standing or Existence obtained in the last 60 days.
Operating without registering can mean a ban on suing in Illinois courts until it registers (805 ILCS 180/45-45(a)); back fees.
Quoted: ilga.gov (pulled October 2026, noted here)
The do-it-yourself total
No service means three years of state fees at $300. Hiring one adds $397 to $497 in the same period.
Frequently asked
How much does it cost to register a foreign LLC with Illinois?
$150 at the filing office, before service fees of $199.
What do these services cost over three years?
$397 to $497 in service fees, before state fees.
What form registers the LLC?
The registration is Application for Admission to Transact Business (Form LLC-45.5), filed with the Illinois Secretary of State, Department of Business Services, Limited Liability Division.
Does Illinois ask for a certificate from the home state?
Yes, no more than 60 days old: certificate of Good Standing or Existence.
What recurring filing comes after registration?
It is the annual report, at $75.
In what year does one service become pricier than another?
Not in the next ten years. The running totals keep their order.
Which foreign registration service is the best value for Illinois?
Best to least: IL Registered Agent.org, Mainstay Filing and Illinois Registered Agent.co.