GC Laws — Illinois contractor-law checklist preview (free)
Sources reviewed 2026-09-30. Public summaries remain free on gclaws.com.

[ ] Licensing
      - Illinois does not require a statewide general-contractor license or certification, according to the Attorney General’s contractor guidance. Local governments may impose contractor requirements and permits. Roofing contractors require state licensing through IDFPR, and plumbers are licensed through the Illinois Department of Public Health. Verify both the local requirements and the state credential for the trade involved.

[ ] Mechanic's liens
      - To enforce against or to the prejudice of another creditor, encumbrancer or purchaser, an original contractor must bring suit or record the verified claim within four months after completing the work or furnishing the last extra work or materials. Section 7 prescribes the credited amount, contract description, owner and sufficiently identifying property description.
      - As against the owner, §7 states a two-year period after completion. The four-month rule protects priority against third parties and should not be replaced by a universal two-year filing instruction.

[ ] Retainage
      - For covered private construction contracts, Illinois permits retainage of up to 10% of payments before 50% completion. At 50% completion, accumulated retainage must be reduced so no more than 5% is held; later payments may have no more than 5% retained. The Contractor Prompt Payment Act excludes contracts spending public funds, single-family residences and multifamily residences with 12 or fewer units in one building.

[ ] Prompt payment
      - For contract-compliant work and an approved payment application, the owner must pay within 15 calendar days after approval. Approval is deemed after 25 days from receipt unless the owner supplies a timely written withheld amount and reason.
      - For contract-compliant, accepted subcontract work, each contractor/subcontractor must pass through the corresponding payment, including final payment and retainage, within 15 calendar days of receipt.

[ ] Prevailing wage
      - The Act covers the defined public works, including fixed works constructed or demolished by a public body or paid for wholly or partly with public funds, together with the other categories specified in §2.
      - Covered laborers, workers and mechanics employed by or for a public body in public works receive no less than the prevailing hourly wage for similar work in the locality under §3.

[ ] Davis-Bacon (federal)
      - Under 40 U.S.C. section 3142, covered contracts require payment to laborers and mechanics employed directly on the site of the work at least weekly, at rates no lower than the applicable prevailing wage determination. The required compensation includes the basic hourly rate and required fringe benefits, which may be provided through qualifying benefits or cash as the statute permits.
      - Qualifying apprentices may receive a lower registered-program rate only when the applicable registration and program conditions are met. The Department of Labor’s apprenticeship rules govern those exceptions.
      - The Department of Labor determines the prevailing rates for the work classifications and locality. Contractors and subcontractors must use the wage determination applicable to their covered contract.
      - Federal assistance alone does not establish coverage: many, but not all, construction-assistance statutes include Davis-Bacon requirements. Identify the funding program and its governing Related Act.
      - SAM.gov publishes Davis-Bacon wage determinations. Search by the wage-determination number or the Davis-Bacon public-buildings-or-works category, and match the decision to the contract, locality, and work classification.

This preview lists the topics and rules covered in the full state pack. The paid pack adds the complete source URLs, citations, review dates, and the three editable tools.
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