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Letting 101: A guided tour through IDOT's bid letting process

IDOT Blog – Tuesday, May 10, 2022

Over the course of the year, the Illinois Department of Transportation has seven regularly scheduled lettings, representing more than a thousand transportation infrastructure projects throughout the state annually. Thanks to Gov. JB Pritzker and his historic Rebuild Illinois capital program, the number of projects happening in Illinois has significantly increased.

With the increase in projects, IDOT strives to level the playing field, providing minorities, women and other eligible small businesses an opportunity to take part in rebuilding Illinois through the Disadvantaged Business Enterprise (DBE) Program. Learn more about the DBE program and the resources IDOT provides to both established and emerging businesses here.

But what is a bid letting? Essentially, a letting is a five- or six-week period when road, bridge, aeronautics and various other construction projects are available for bidding. Contractors, subcontractors, materials suppliers and transportation industry groups may review and bid on the projects. The process is governed by strict statutory guidelines. Our schedule highlights important deadlines throughout the letting period.

Significant stages of the letting process include:

  • Identifying projects in the advanced stages of design, along with funding and schedules for implementing them occurs with the transportation improvement programs. The first step in assigning projects to a specific letting.
  • The “Transportation Bulletin” is published and posted five weeks prior to the letting as an “Invitation for Bids” to the bidding public.
  • Prequalification with IDOT is required for most projects. The prequalification “cut off” is the deadline for a bidder to submit a prequalification application.
  • The joint venture cut off is the deadline for bidders to submit the “Certificate of Joint Venture.” Joint ventures allow prequalified contractors to combine their available bidding capacity and request authorization to bid for a single project together, pending departmental approval.  
  • To become authorized to bid on projects, bidders must submit the “Request for Authorization to Bid” and provide the “Affidavit of Availability” (for projects that require prequalification) on or before the cut-off date shown on the letting schedule.
  • On letting day at noon, all sealed bids are opened publicly. A low bidder is identified, and the “As Accepted Tabulation of Bids” is posted to the website for public viewing. This final step also includes subsequent documentation reviews as the project award process begins and each project advances to on-site construction needs.

If you are new to the IDOT bid letting process or need updated information, following are some

 helpful resources:

Stay tuned for more about what is happening in the current letting phase. Be sure to check out our new section in the IDOT Telegram dedicated to letting information for upcoming stage dates, special bid opportunities and more. This new section will be located below our District Updates.

Subscribe at IDOT in Motion to get the Telegram and more.