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Estimating & Bidding

Bidder

In Plain English

A contractor who submits a price to compete for a construction project.

Definition

A bidder is a contractor or entity that submits a bid in response to an invitation to bid or request for proposals. To be eligible for award, a bidder must typically be both responsive and responsible. The term applies before award; after award, the successful bidder becomes the contractor.

Why It Matters in Bidding

Whether a firm is treated as a qualified bidder determines its eligibility for award, since being low means nothing if the bid is nonresponsive or the firm is judged not responsible. Understanding bidder obligations, from bid bonds to required forms, lets an estimator submit a complete, defensible proposal that survives scrutiny after opening.

Example

Before submitting on a school district project, an estimator confirms his firm is a qualified bidder by verifying prequalification status, attaching the bid bond, and completing every required form so the proposal cannot be rejected as nonresponsive.

Related Terms

Responsive BidderResponsible BidderBidCompetitive Bidding

Frequently Asked Questions

Responsive means the bid itself complied with the invitation, including required forms, bonds, pricing format, and signatures. Responsible refers to the firm's capability, covering experience, financial strength, bonding capacity, and past performance. A bidder must satisfy both tests to be eligible for award, even when its price is lowest.
It depends on the documents. Some invitations make the pre-bid meeting or site walk mandatory, and a bidder who skips a required meeting may be disqualified. Even when optional, attending helps a bidder understand site conditions and scope clarifications that affect takeoff accuracy and competitiveness.
A firm is a bidder during the procurement phase, from submitting its price through evaluation. Once the owner issues a notice of award and the parties execute the contract, the successful bidder becomes the contractor and assumes the obligations to perform the work under the agreed terms.

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