Where to bid: state, county and city bid portals
Every state posts its bids on its own portal, and so do counties and cities. This directory lists each state's portal and the bid pages of 2952 counties and 3051 cities and towns of 10,000+ people: which platform each runs on and where vendors register. Federal opportunities are on Open now; the state and local bids SpendQuery loads itself are on Local bids.
Most used platforms here: Tyler Munis self service (125), BidNet Direct (115), OpenGov Procurement (76), Bonfire (Euna Procurement) (55), PlanetBids (52), QuestCDN (41), DemandStar (38), IonWave (29), Public Purchase (20), Vendor Registry (19), Bid Express (9), Oracle supplier portal (8).
How it's built: states by hand; counties and cities from the Census Bureau's 2023 population estimates, their official sites from the .gov registry and Wikidata, and each site read once for its bid page (robots.txt obeyed; sites that block automated checks are left for a person to check). Links go to the governments' own portals. A missing or wrong link?