Illinois Foreign LLC Fees (2026): Data on File and the 3 Best Services
Illinois 2026, a foreign LLC registration: the desk ranks Mainstay Filing ($199), Illinois Registered Agent.co ($199) and IL Registered Agent.org ($199), in that order. Registration: $150 at the Illinois Secretary of State, Department of Business Services, Limited Liability Division; $75 per report after that. Three-year rank: 28th of 50.
Order set by five weighted criteria (see method): three-year service fees 31%, filings covered 29%, then renewal, fit with Illinois rules and fee transparency.
1. Mainstay Filing: best for expanding across state lines
Top ranked$199 plus state fee; agent $149/yr from yr 2
We rank Mainstay Filing first. Reason: $199 over the state fee, registered agent free in year one, then $149 a year.
Over three years it costs $100 more than Illinois Registered Agent.co. Coverage carries 29%, and the extra filings handled outweigh the gap.
From the second year, agent service is $149 a year.
What the fee covers
Registration filed on your behalf
Registered agent: no fee in year one
Serves all fifty states
Pros
All fifty states covered
$199 over the state fee
First agent year covered
Cons
Agent renews at $149, $50 above Illinois Registered Agent.co
$150 plus the Application for Admission to Transact Business (Form LLC-45.5), to the Illinois Secretary of State, Department of Business Services, Limited Liability Division. Also required: certificate of Good Standing or Existence, at most 60 days.
Then each cycle the annual report ($75), within the 60 days before your anniversary month.
Have ready
Certificate of Good Standing or Existence, not more than 60 days.
Name and formation date as the home state lists them.
A registered agent with a street address here; each service on this page supplies one.
A way to pay the $150 registration fee.
Cost of not registering
State courts will not hear a suit from an unregistered LLC (805 ILCS 180/45-45(a)). Contracts are not voided (805 ILCS 180/45-45(b)). Expect a bill for back fees.
Basis for the order
Deciding criterion for Illinois: scope of the price, at 29%.
Reach across states outweighed Illinois Registered Agent.co's smaller renewal.
Questions
Fee for a foreign LLC to register in Illinois?
$150 as the official fee. Hiring one adds $199.
Foreign registration form for Illinois?
Use the Application for Admission to Transact Business (Form LLC-45.5); it goes to the Illinois Secretary of State, Department of Business Services, Limited Liability Division.
Home-state certificate required?
Yes: certificate of Good Standing or Existence, dated within 60 days of filing.
Anything due yearly from a foreign LLC?
Yes, the annual report, fee $75.
What if the LLC works there unregistered?
State courts will not hear a suit from an unregistered LLC (805 ILCS 180/45-45(a)). Contracts are not voided (805 ILCS 180/45-45(b)). Expect a bill for back fees.
Illinois: a registered agent for a foreign LLC?
Every LLC must name a registered agent with an in-state street address.
Which service do you pick for foreign registration?
Rank Mainstay Filing first (it files the Illinois registration for $199 on top of the state fee, first agent year included), then Illinois Registered Agent.co and IL Registered Agent.org.