3 Best LLC Services in Illinois (2026): Prices Tracked
Our 2026 watchlist puts IL Registered Agent.org ($199), Illinois Registered Agent.co ($199) and Mainstay Filing ($199) at the top for LLC formation services in Illinois, listed in that order. The three-year total for services spans $397 to $597; the state's $150 to file is a separate charge.
Tracked by the Filing Price Watch editorial team
Ordered by:
Best value first, using our five measures
Illinois in numbers
Formation fee at the state office$150ilsos.gov (pulled October 2026, noted here)
First-year price range$199Service fees alone
Total after 3 years$397 to $597Three years of provider charges
State fees by year three$300Official figures only
Break-evenDoes not happenStable for a decade
Ranked picks
Service prices only. The $150 state fee applies to every service.
#Ordered byPrice in year 1Price at renewalThree-year spend
1
Best value
1. IL Registered Agent.org: best for a stripped-down formation
$199 plus the state's fee, then $99 a year
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 it costs $199 to form with a first agent year included, and later years are $99.
Cost decides this one: three years here total less than three years with Mainstay Filing.
You file the Limited Liability Company Annual Report on your own.
Price covers
Formation paperwork done
A year of agent service to begin with
Holds up
$99 a year from year two
Year-one agent covered
Forming costs $199
Weak spots
The Limited Liability Company Annual Report is not priced in
$99 extra for the EIN
2
Home-state provider
2. Illinois Registered Agent.co: best for owners who file their own reports
$199 plus the state's fee, then $99 a year
Price in year 1$199
Price after year 1$99/yr
Three-year spend$397
Illinois Registered Agent.co takes spot 2 because it costs $199 to form with a first agent year included, and later years are $99.
You file the Limited Liability Company Annual Report on your own.
Its prices are identical to IL Registered Agent.org's.
Price covers
Formation paperwork done
A year of agent service to begin with
Holds up
Year-one agent covered
Forming costs $199
$99 a year from year two
Weak spots
The Limited Liability Company Annual Report is not priced in
$99 extra for the EIN
3
Works in every state
3. Mainstay Filing: best for forming and maintaining under one price
$199 a year, renewing at the same $199
Price in year 1$199
Price after year 1$199/yr
Three-year spend$597
Entry 3 is Mainstay Filing. It is the only price here that folds the annual report into $199 a year.
A $200 gap to IL Registered Agent.org at year three decides where it sits.
The Limited Liability Company Annual Report is handled each time, with Illinois's $75 passed along at cost.
Price covers
Formation of the LLC
Registered agent for the full year
Annual report, filed when it is due
EIN application, prepared for you
State fee billed as is
Holds up
EIN application included
Price does not rise at renewal ($199)
Stays at $199
Weak spots
$100 a year over IL Registered Agent.org from year two
For the state side of three years we add up the filing fee, the report charged in years two and three and a yearly minimum tax if the state has one. Publication requirements and other open-ended costs are noted in the text, not totaled.
What decided the order
In Illinois, tracked three-year cost (37% of the order) was the measure where IL Registered Agent.org pulled ahead.
IL Registered Agent.org wins the cost measure at $397 for three years, $200 under what Mainstay Filing charges.
If you count the EIN application, IL Registered Agent.org costs less from year 2.
Illinois LLC filing fee and requirements, as written by the state
To form it: the Articles of Organization (Form LLC-5.5), $150, sent to the Illinois Secretary of State. Every LLC must name a registered agent with an in-state street address.
Official text: ilsos.gov (pulled October 2026, noted here)
Skipping the service
Filing on your own costs $300 in state fees over three years. The $397 to $597 charged by services pays for not doing the forms.
Questions and answers
How much do LLC formation services cost in Illinois?
Year one is $199 among these services, and Illinois adds $150 to file.
What do these services cost over three years?
Three years of service run $397 to $597.
What does Illinois charge to file an LLC?
$150 along with the Articles of Organization (Form LLC-5.5).
What does Illinois charge every year once the LLC exists?
Limited Liability Company Annual Report: $75 a year, and the deadline reads before the first day of the entity's anniversary month.
Does the price include the EIN application?
It depends on the service: IL Registered Agent.org ($99), Illinois Registered Agent.co ($99) and Mainstay Filing (included).
In what year does one service become pricier than another?
Not in the next ten years. The running totals keep their order.
Which LLC formation service is the best value in Illinois?
IL Registered Agent.org is first, Illinois Registered Agent.co second, and Mainstay Filing third.