How do Illinois mechanics lien deadlines affect a construction dispute?

Illinois mechanics liens are governed by the Mechanics Lien Act (770 ILCS 60), which sets strict deadlines that can determine whether a lien is valid at all. Among them, a subcontractor generally must serve a 90-day notice measured from its last date of furnishing labor or materials, a contractor generally must record the lien within four months of last furnishing to preserve priority against third parties, and an enforcement suit generally must be filed within two years — a period that can be shortened by a statutory demand. A recent change, effective January 1, 2025, expanded the permitted methods for serving the subcontractor notice to include nationally recognized tracked delivery services such as FedEx and UPS. Critically, agreeing to mediate does not pause these statutory deadlines, so parties should mediate promptly rather than let a lien deadline lapse while negotiations continue.