Registered Agent by ZIP › Illinois
Registered agent in Illinois (2026)
Illinois ZIP codes begin with 600-620, 622-629. Required: every LLC needs an agent with an in-state street address Mainstay Filing, our best overall pick, serves Illinois at $149 a year; the state fee to change agents is $25.
- Illinois rules checked October 20, 2026
Illinois agent requirements
- Requirement
- Required. An Illinois resident, or a business authorized to do business in Illinois. The LLC cannot act as its own agent.
- Agent address
- 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.
- ZIP code prefixes
- 600-620, 622-629
- Change-of-agent fee
- $25
- Statute
- 805 ILCS 180/1-35
- Filing office
- Illinois Secretary of State
Mainstay Filing
Our rating: 4.9 out of 5
$149 / year, same at renewal
- Registered agent address in Illinois
- Mail and legal-document scanning and forwarding
- Compliance reminders
Checked October 20, 2026.
Providers with a published Illinois price
| Provider | Year 1 | Renewal |
|---|---|---|
| Mainstay Filing | $149 | $149 |
| Harbor Compliance | $99 | $159 |
| InCorp Services | $129 | $129 |
| Northwest Registered Agent | $125 | $125 |
| FreeRegisteredAgent.com | $0 | $129 |
| ZenBusiness | $99 | $199 |
| Registered Agents Inc | $200 | $200 |
| Bizee | $149 | $149 |
| LegalZoom | $249 | $249 |
Questions
Who can be a registered agent in Illinois?
An Illinois resident, or a business authorized to do business in Illinois. The LLC cannot act as its own agent.
What address must a Illinois registered agent have?
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.
What does it cost to change registered agents in Illinois?
The state charges $25 to file the change (805 ILCS 180/1-35).
Which ZIP codes are in Illinois?
Illinois ZIP codes begin with 600-620, 622-629. The ZIP code tells you the state; the agent rules above apply in all of them.
Sources
- Illinois registered agent statute (805 ILCS 180/1-35): www.ilga.gov/legislation/ilcs/fulltext.asp?DocName=080501800K1-35, checked October 20, 2026
- Illinois Secretary of State: www.ilsos.gov/, checked October 20, 2026
- Provider registered agent pages (prices), checked October 20, 2026