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LLC 101 Guide

Unit 2 · Illinois

The Illinois Registered Agent Unit (2026): 6 Tasks and the 3 Best Agents

Our 2026 Illinois picks for naming a registered agent, strongest to weakest, are Illinois Registered Agent.co ($99 a year), IL Registered Agent.org ($99 a year) and Mainstay Filing ($149 a year). Work through the 6 tasks and your registered agent will be appointed the right way.

Prepared by the LLC 101 Guide instructors

Read this first

Is a registered agent required?
Yes
Look it up at ilga.gov; our reading dates from October 2026
Service prices
$99 to $149 a year
From company pricing pages
Limited Liability Company Annual Report
$75 a year
Look it up at ilsos.gov; our reading dates from October 2026
Task count
6
From first to last

By the end you will know

  • The legal requirement
  • The address and eligibility rules
  • Getting the agent listed
  • The agents at the top of the class

The Illinois honor roll

Graded on the grading page: three-year cost (34%), assignments completed (31%), renewal price, fit with Illinois's rules and plain pricing.

Top of the class

1. Illinois Registered Agent.co: best for one-state companies

Our first pick$99 a year, unchanged at renewal

Illinois Registered Agent.co earns the top grade in Illinois: $99 a year with no bump at renewal, a good match for an LLC that stays in one state.

A smaller three-year total than Mainstay Filing earns it first place; cost counts 34%.

What the price covers

  • A registered office address
  • Online copies of legal papers

What works

  • Yearly price below the national pick
  • Price $99; renews at $99

What to weigh

  • Serves Illinois alone
  • Limited Liability Company Annual Report stays your job
Visit Illinois Registered Agent.coPartner link. We may earn money if you buy.

Top of the class

2. IL Registered Agent.org: best for a local alternative

One-state plan$99 a year, unchanged at renewal

Our second choice, IL Registered Agent.org: $99 a year with no bump at renewal, a good match for an LLC that stays in one state.

It lists the same prices as Illinois Registered Agent.co.

What the price covers

  • A registered office address
  • Online copies of legal papers

What works

  • Yearly price below the national pick
  • Price $99; renews at $99

What to weigh

  • Serves Illinois alone
  • Limited Liability Company Annual Report stays your job
Visit IL Registered Agent.orgPartner link. We may earn money if you buy.

Top of the class

3. Mainstay Filing: best for a nationwide agent under one price

Does most of the work$149 a year, unchanged at renewal

Our third choice, Mainstay Filing: one flat $149 yearly price that does not depend on which state the LLC sits in.

Counted over three years, it trails Illinois Registered Agent.co by $150.

What the price covers

  • A Illinois street address for the record
  • Free scans of legal papers served on the company, sent the business day they arrive
  • Up to three government letters a year are scanned free
  • Also works for nonprofits, corporations, LPs and LLPs

What works

  • The same provider anywhere
  • $149 each year, no increase

What to weigh

  • Costs $50 extra every year
  • Agent service and nothing more
Visit Mainstay FilingPartner link. We may earn money if you buy.

Grades and prices together

#ServiceAnnual priceRenewal priceThree-year total
1Illinois Registered Agent.co$99$99/yr$297Visit Illinois Registered Agent.coPartner link. We may earn money if you buy.
2IL Registered Agent.org$99$99/yr$297Visit IL Registered Agent.orgPartner link. We may earn money if you buy.
3Mainstay Filing$149$149/yr$447Visit Mainstay FilingPartner link. We may earn money if you buy.
Listed prices, read November 13, 2026. Switching agents does not change what the state charges.

The tasks

  1. Task 1

    Learn the requirement

    Every LLC must name a registered agent with an in-state street address.

    Source: Look it up at ilga.gov; our reading dates from October 2026

  2. Task 2

    Check who is eligible

    An Illinois resident, or a business authorized to do business in Illinois. The LLC cannot act as its own agent. Legal source: 805 ILCS 180/1-35.

  3. Task 3

    The address rule

    The address has to be a registered office in Illinois that matches the agent's business office. A P.O. box alone is not accepted.

    Every recommended service provides the Illinois office address.

  4. Task 4

    Choose between acting alone and hiring

    Hiring from the recommended agents costs $99 to $149 a year; serving yourself is the option for those who qualify.

  5. Task 5

    Get the agent listed publicly

    A new company names its agent when it files the Articles of Organization (Form LLC-5.5); to replace the agent later, file again with the Illinois Secretary of State.

    Source: Look it up at ilsos.gov; our reading dates from October 2026

  6. Task 6

    Check the record every year

    The Limited Liability Company Annual Report costs $75 every year and is due before the first day of the entity's anniversary month; any notice about it comes through the registered agent.

    Source: Look it up at ilsos.gov; our reading dates from October 2026

The bill

What forPaid toSum
Registered agent serviceThe provider$99 to $149 a year
Renewing the agentThe provider$99 to $149 a year
Limited Liability Company Annual ReportState agency$75 every year
State amounts come from Illinois's official fee schedules (see the sources below); service prices come from each company's site. The three-year state total adds the filing, the reports for years two and three and any minimum tax.

How the grades came out

Course fee across three years makes up 34% of the grade, and that is where got ahead in Illinois.

Illinois Registered Agent.co costs $297 for years one to three, while Mainstay Filing costs $150 more.

Illinois questions

Is an LLC in Illinois obliged to keep a registered agent?

Yes. Every LLC must name a registered agent with an in-state street address.

Can I be my own registered agent?

An owner can serve if qualified; tasks 2 and 3 hold the tests.

Can I change my registered agent later?

Change whenever you like, through the Illinois Secretary of State, as task 5 describes.

What does a registered agent cost in Illinois?

Our recommended agents charge $99 to $149 a year.

What does the LLC pay the state each year?

The LLC sends in the Limited Liability Company Annual Report for $75 every year.

Which registered agent would you choose?

Illinois Registered Agent.co is first, IL Registered Agent.org and Mainstay Filing follow, and Illinois Registered Agent.co wins on course fee across three years.

Reading list and sources

  1. Reading list entry for Illinois Secretary of State, Department of Business Services: ilsos.gov, reread August 2026, the document behind these numbers.
  2. Reading list entry for Illinois Secretary of State, Department of Business Services: ilsos.gov, reread August 2026, the document behind these numbers.
  3. Reading list entry for 805 ILCS 180/5-5: ilga.gov, reread August 2026, the document behind these numbers.
  4. Reading list entry for Illinois formation fee: Filing fee, official source: ilga.gov, reread October 2026, the document behind these numbers.
  5. Reading list entry for Illinois formation fee: Filing fee, official source: ilsos.gov, reread October 2026, the document behind these numbers.
  6. Reading list entry for Illinois registered agent statute: ilga.gov, reread October 2026, the document behind these numbers.
  7. Illinois Registered Agent.co: pricing page, as seen on November 13, 2026
  8. IL Registered Agent.org: pricing page, as seen on November 13, 2026
  9. Mainstay Filing: Illinois service page, as seen on November 13, 2026