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Illinois • Mechanics Lien Deadlines

Illinois Mechanics Lien Deadline Calculator

Learn the exact preliminary notice and lien filing deadlines in Illinois. Then jump into the LienDeadline calculator to see your real project dates in 0.3 seconds.

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Illinois Lien Deadline Overview

Preliminary Notice Deadline

Must serve notice within 90 days of last furnishing

Mechanics Lien Filing Deadline

4 months after last furnishing labor or materials

Typical Projects

Building material suppliers, lumber yards, concrete and rebar suppliers working on private construction projects in Illinois.

This page is a simplified summary for material suppliers and does not replace advice from a construction attorney.

How lien deadlines work in Illinois

In Illinois, material suppliers must follow specific deadlines to protect their lien rights. The preliminary notice deadline is must serve notice within 90 days of last furnishing. The mechanics lien filing deadline is 4 months after last furnishing labor or materials. Missing either deadline results in complete loss of lien rights for that project.

Preliminary notice rules

  • Must serve Notice of Lien Claim within 90 days of last work
  • Must serve notice within 90 days of last furnishing
  • Notice of Lien Claim required for material suppliers

Mechanics lien filing rules

  • Must serve Notice of Lien Claim within 90 days of last work
  • Lien must be filed within 4 months of last furnishing
  • 4 months after last furnishing labor or materials

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Enter your Illinois project dates once. LienDeadline shows you preliminary notice and lien filing deadlines in 0.3 seconds across all supported states.

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Frequently asked questions

What is the mechanics lien deadline in Illinois?

4 months after last furnishing labor or materials

Does Illinois require a preliminary notice?

Must serve notice within 90 days of last furnishing

What happens if I miss the deadline?

You lose your legal right to file a lien for that project, even if you're still owed money. That's why many suppliers use automated deadline tools instead of spreadsheets.