Addendum

An addendum is a buyer-issued amendment to a solicitation that changes, clarifies, or adds to the requirements — and it becomes part of the contract documents, equal in force to the original text.

Missing an addendum is a classic disqualification: responding to superseded requirements reads as non-compliance, and bids are rejected for it. Acknowledge every addendum where the instructions require it — some solicitations ask for a signed acknowledgement sheet per addendum, others fold it into the form of tender. Addenda also move deadlines and occasionally change the evaluation; when one lands, the compliance matrix gets re-walked against the amended documents, not filed for later. A late addendum that materially changes scope is also a legitimate reason to revisit bid/no-bid.

@misc{pi-2026-definitions-addendum,
  author = {{The Procurement Institution}},
  title  = {Addendum — definition},
  year   = {2026},
  url    = {https://procurementinstitution.org/definitions/addendum},
  note   = {Release 2026.10}
}