Open tenders · Ontario
Open Ontario government construction tenders
128 open public construction tenders in Ontario right now, scanned daily from MERX, CanadaBuys, and municipal portals like the City of Toronto.
Updated October 21, 2026.
Open now
128
New in last 30 days
108
Showing
121–128
Closing soonest
General Contractor Services QRT Source List
636 days leftDefence Construction Canada - Ontario RegionKingston-Pembroke, ONCloses Jul 17, 2028via OntarioProcurementSource list: Prequalification: suppliers apply to join the buyer's list, and the buyer later invites suppliers on it to bid.
General ContractorView on official portal →Civil/Municipal Contractor Services Source List
639 days leftDefence Construction Canada - Ontario RegionKingston-Pembroke, ONCloses Jul 20, 2028via OntarioProcurementSource list: Prequalification: suppliers apply to join the buyer's list, and the buyer later invites suppliers on it to bid.
CivilView on official portal →Mechanical Contractor Services Source List
639 days leftDefence Construction Canada - Ontario RegionKingston-Pembroke, ONCloses Jul 20, 2028via OntarioProcurementSource list: Prequalification: suppliers apply to join the buyer's list, and the buyer later invites suppliers on it to bid.
MechanicalView on official portal →General Contractor Services Source List
639 days leftDefence Construction Canada - Ontario RegionKingston-Pembroke, ONCloses Jul 20, 2028via OntarioProcurementSource list: Prequalification: suppliers apply to join the buyer's list, and the buyer later invites suppliers on it to bid.
General ContractorView on official portal →Electrical Contractor Services Source List
639 days leftDefence Construction Canada - Ontario RegionKingston-Pembroke, ONCloses Jul 20, 2028via OntarioProcurementSource list: Prequalification: suppliers apply to join the buyer's list, and the buyer later invites suppliers on it to bid.
ElectricalView on official portal →Mechanical Contractor Services QRT Source List
934 days leftDefence Construction Canada - Ontario RegionKingston-Pembroke, ONCloses May 11, 2029via MERXSource list: Prequalification: suppliers apply to join the buyer's list, and the buyer later invites suppliers on it to bid.
MechanicalView on official portal →QRT Civil Contractor Services SL
994 days leftDefence Construction Canada - Ontario RegionKingston-Pembroke, ONCloses Jul 10, 2029via MERXSource list: Prequalification: suppliers apply to join the buyer's list, and the buyer later invites suppliers on it to bid.
CivilView on official portal →- Humber PolytechnicToronto, ONCloses Oct 8, 2030via MERXElectricalView on official portal →
Showing tenders 121–128 of 128 open, soonest closing first. Start free to see them scored to your profile →
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Frequently asked questions
- How often is this list of Ontario tenders updated?
- Cornerstone scans Ontario's public procurement sources every day, and this page refreshes hourly — so the list reflects what's open right now. The "updated" date shows the most recent refresh.
- Is it free to browse Ontario government tenders here?
- Yes. Browsing open tenders is free and needs no account. A free Cornerstone account adds matching to your trade, geography, and bonding capacity, plus AI-drafted bid proposals — but the listings themselves are public.
- Where do these Ontario tenders come from?
- Public procurement portals — MERX, CanadaBuys, and municipal portals like the City of Toronto — plus municipal sites. Each listing links to the official source posting, where you submit your bid directly.
Listings aggregated from public procurement portals; each links to its official source. This page is general information, not procurement advice — always confirm requirements in the official tender documents.