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Registered agent worksheets · Illinois

3 Best Registered Agents in Illinois (2026): Worked Prices

The 2026 math for Illinois registered agents gives Mainstay Filing ($149/yr), Illinois Registered Agent.co ($99/yr) and IL Registered Agent.org ($99/yr), ranked best value first. Agent service adds up to $297 to $447 over three years, beginning at $99 to $149.
Worked by the Formation Math editorial team

↓ Sorted by: Best score first, from five weighted checks

Illinois in brief

Agent requirement Yes ilga.gov (checked October 2026) as the source
Totals after one year $99 to $149 Cost of one year
Three-year spread $297 to $447 Opening price and two renewals
Limited Liability Company Annual Report $75 a year ilsos.gov (checked October 2026) as the source
Break-even year No crossing No change in order

Worksheet: Illinois

Rows are sorted by the method. No state fee depends on the agent.

1
Highest score

1. Mainstay Filing: best for nationwide coverage

$149 first year, $149 after
Year-1 price $149
Renewal price $149/yr
Sum of 3 years $447

Mainstay Filing scores highest in Illinois: $149 a year here and exactly $149 in any other state.

Subtract and Illinois Registered Agent.co is $150 cheaper across three years, yet it leaves more filings to you.

The price buys

  • A street address in the state
  • Three government mailings per year, scanned for free
  • Works for LLCs, corporations, LPs, LLPs and nonprofits

Adds up

  • $149 a year, flat at renewal
  • Works in every state

Does not add up

  • $50 more a year than Illinois Registered Agent.co
  • Covers the agent role only
2
Illinois only

2. Illinois Registered Agent.co: best for the smallest annual agent total

$99 first year, $99 after
Year-1 price $99
Renewal price $99/yr
Sum of 3 years $297

Illinois Registered Agent.co is row 2: $99 a year, $99 when it renews, for an LLC that never leaves the state.

The price buys

  • An address in the state on file
  • Scans of papers served on the LLC

Adds up

  • Smaller yearly bill than Mainstay Filing
  • $99 annually, no increase

Does not add up

  • Illinois only
  • This row does not reach the Limited Liability Company Annual Report
3
Illinois only

3. IL Registered Agent.org: best for staying entirely local

$99 first year, $99 after
Year-1 price $99
Renewal price $99/yr
Sum of 3 years $297

IL Registered Agent.org is row 3: $99 a year, $99 when it renews, for an LLC that never leaves the state.

Illinois Registered Agent.co publishes the same prices.

The price buys

  • An address in the state on file
  • Scans of papers served on the LLC

Adds up

  • $99 annually, no increase
  • Smaller yearly bill than Mainstay Filing

Does not add up

  • Illinois only
  • This row does not reach the Limited Liability Company Annual Report

Totals after 1, 2, 3 and 5 years

No. Provider Year 1 total Total at year 2 Total at year 3 Total at year 5
1 Mainstay Filing $149 $298 $447 $745 Visit Mainstay Filing Partner link. We may earn money if you buy.
2 Illinois Registered Agent.co $99 $198 $297 $495 Visit Illinois Registered Agent.co Partner link. We may earn money if you buy.
3 IL Registered Agent.org $99 $198 $297 $495 Visit IL Registered Agent.org Partner link. We may earn money if you buy.

Company prices from November 13, 2026, summed year by year. The totals keep one order for ten years.

Break-even check

How many years will you keep the company? Choose and compare.

Total over 3 years: Mainstay Filing $447, Illinois Registered Agent.co $297, IL Registered Agent.org $297. The least spent: Illinois Registered Agent.co.

Illinois fee schedule

Term Value Where it comes from
Filing the articles $150 ilsos.gov (checked October 2026) as the source
Limited Liability Company Annual Report $75 every year ilsos.gov (checked October 2026) as the source
Late fee $100 ilsos.gov (checked October 2026) as the source
State fees added over 3 years $300 Total of the rows

Working: filing fee, plus the recurring report in years two and three, plus any minimum tax. The sum is the three-year state line.

The working behind Illinois

For Illinois, the term that decided it was items covered per dollar (28% of the score), where Mainstay Filing came out ahead.

Coverage lifted it above Illinois Registered Agent.co.

Illinois registered agent rules, from the source (Illinois Secretary of State)

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

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

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.

As written: ilga.gov (checked October 2026) as the source

If you skip the service

An owner who meets the address rule can serve for free; the rows above put a price of $99 to $149 a year on the convenience.

About these figures

What does a registered agent in Illinois cost per year?

About $99 to $149 yearly.

What do three years of agent service cost?

Year one plus two renewals gives $297 to $447.

Does Illinois require a registered agent for an LLC?

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

Can the owner be the registered agent?

Yes, if you meet the eligibility and address rules above.

What does the state collect from the LLC each year?

$75 annually for the Limited Liability Company Annual Report, deadline given as before the first day of the entity's anniversary month.

In what year does one service pass another in total cost?

Never in ten years: the order of the running sums does not change.

Which registered agent is best value in Illinois?

By the five-part score the Illinois rows run Mainstay Filing, Illinois Registered Agent.co and IL Registered Agent.org, led by Mainstay Filing on items covered per dollar.

More worksheets

Registered agent worksheets, all 50 states Best registered agents overall The method

Inputs and sources

  1. Check Illinois Secretary of State, Department at ilsos.gov; last read August 2026.
  2. Check Illinois Secretary of State, Department at ilsos.gov; last read August 2026.
  3. Check 805 ILCS 180/5-5 at ilga.gov; last read August 2026.
  4. Check Illinois formation fee: Filing fee at ilga.gov; last read October 2026.
  5. Check Illinois formation fee: Filing fee at ilsos.gov; last read October 2026.
  6. Check Illinois registered agent statute at ilga.gov; last read October 2026.
  7. Prices from Mainstay Filing, Illinois service page, November 13, 2026
  8. Prices from Illinois Registered Agent.co, pricing page, November 13, 2026
  9. Prices from IL Registered Agent.org, pricing page, November 13, 2026