Illinois · Government contracting
Illinois Government Contracts & Bid Opportunities
Last reviewed August 14, 2026 · How we source this
Illinois posts state opportunities through a procurement bulletin and a central eProcurement system, with highway work bid by IDOT and state buildings managed by the Capital Development Board. Chicago and Cook County run their own large procurement operations, and Illinois has strong prevailing-wage requirements.
Where Illinois opportunities are posted
- Illinois Procurement Bulletin & BidBuy
The Procurement Bulletin lists state solicitations; BidBuy is the state's eProcurement system where vendors register and respond.
- IDOT construction
The Illinois Department of Transportation bids highway and roadway construction and requires prequalification.
- Capital Development Board (CDB)
Manages state building construction — a primary channel for vertical construction trades.
Major buyers in Illinois
- Illinois Department of Transportation (IDOT) — Highways and roadways — prequalification required; civil and heavy construction.
- Capital Development Board (CDB) — State building construction.
- Chicago, Cook County & school districts — Chicago and Cook County run their own large procurement operations, alongside counties and districts statewide.
How to register as a vendor in Illinois
Register in Illinois BidBuy and monitor the Illinois Procurement Bulletin for state solicitations. IDOT and the Capital Development Board may require prequalification. Chicago and Cook County run their own procurement, so register with them directly for local work.
Good to know before you bid in Illinois
- Illinois requires prevailing wages on public works, administered by the Illinois Department of Labor, with certified payroll reporting.
- IDOT requires prequalification for highway construction, and the Capital Development Board manages state building projects.
- Chicago and Cook County operate their own large procurement systems separate from the state.
- Bid, performance, and payment bonds are standard on public construction.
New to the process? Start with How to Win Government Contracts, and keep the glossary handy for any unfamiliar terms.
Illinois government contracting FAQ
Where are Illinois government contracts posted?
Where are Illinois government contracts posted?
State agency solicitations are listed in the Illinois Procurement Bulletin, and vendors register and respond through BidBuy. IDOT bids highway construction separately, the Capital Development Board handles state buildings, and Chicago and Cook County run their own procurement.
Does Illinois require prevailing wages?
Does Illinois require prevailing wages?
Yes. Public-works projects require prevailing wages administered by the Illinois Department of Labor, with certified payroll reporting. Price the correct rates into your bid.
How do I register to bid Illinois state contracts?
How do I register to bid Illinois state contracts?
Register as a vendor in Illinois BidBuy and monitor the Procurement Bulletin for opportunities. For Chicago and Cook County work, register with their separate procurement systems, and complete any IDOT or Capital Development Board prequalification your work requires.
Find Illinois contracts that match your business
GovBid Finder pulls Illinois state and local opportunities alongside federal work and scores each against your profile. Free to use; only pay 3% when you win.