Estimating

What is bid day in construction?

Bid day is the day bids are due on a construction project, when the estimating team collects final subcontractor and supplier quotes, completes the bid form, and submits the price before the deadline.

Two construction professionals review paper plans beside a tablet at a jobsite workbench.
Plan reviews connect field conditions, drawings, and the next decisions on a job. AI-generated illustration.

Bid day is the deadline day for a construction bid, and for most general contractors it is the most hectic day of the estimating cycle. Subcontractors and suppliers hold their best numbers until the last few hours, so the GC's final price comes together in a short window. On a public bid, the deadline is fixed to the minute and late bids are rejected. On private work there is more flexibility, but owners still expect the number on time.

What happens on bid day

Picture a GC bidding a $4.5 million middle school renovation with a 2:00 p.m. deadline. The estimate has been built for three weeks. Bid day runs like this:

Example bid day timeline
TimeWhat happens
7:00 a.m.Confirm all addenda, update the scope sheets, set plugs for trades with no numbers yet
9:00 a.m. to noonSub quotes arrive by email and phone; estimators enter them on leveling sheets
Noon to 1:15 p.m.Final numbers come in; bid leveling picks the carried number per trade
1:15 p.m.Owner or chief estimator reviews totals, sets fee, signs off
1:30 p.m.Bid form completed, bid bond attached, runner leaves or electronic upload starts
2:00 p.m.Deadline. Public bids are opened and read aloud

The 45 minutes between noon and the final review are where jobs are won or lost. A mechanical number that arrives at 12:50 and is $90,000 under the next one might be a great price, or it might be missing the controls scope. Someone has to call and check.

Bid day roles

  • Phone and inbox: one person whose only job is taking calls and logging quotes.
  • Leveling: estimators comparing scope, not just totals, for each trade.
  • Bid form: one person filling out the form, alternates, unit prices, and addendum acknowledgments.
  • Decision maker: the person who sets final fee and signs. Know who that is before 1 p.m.

Common bid day mistakes

  1. Plugging a trade with an old number and forgetting to replace it.
  2. Missing an addendum acknowledgment on the form.
  3. Arithmetic errors in a spreadsheet that has been edited by four people since breakfast.
  4. Not leaving travel or upload time. Electronic bid portals crash and parking garages fill up.
  5. Carrying a too-good-to-be-true number without checking scope. If it gets the job, you may be stuck with it.

Related terms

Bid day depends on a clean bid package, good bid leveling, and an accurate quantity takeoff. Public bids add a bid bond and a sealed bid process. Use the bid leveling template to set up trade sheets ahead of time, and see how to follow up on construction bids for after the deadline.

Frequently asked questions

Why do subcontractors send prices so late on bid day?

Partly to keep their number from being shopped to competitors, and partly because they are bidding many GCs at once. Ask for scope letters early even if the price comes late.

What is a plug number?

An estimated placeholder for a trade with no sub quote yet, often based on past jobs or a budget price. It should be replaced or flagged before submission.

What happens after bid day?

On public jobs, bids are opened and the apparent low bidder is announced. On private jobs, owners often interview the top bidders and negotiate scope before award.

Can I withdraw a bid after bid day?

Rules vary. Public bids usually cannot be withdrawn for a set period after opening except for certain proven mistakes. A bid bond backs that commitment.

Written and edited by

Maurice Francois writes and edits construction operations guides for Smart Business Automator. More from Maurice on the Scaling Legends podcast.

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