FAR 4.1602—Identifying the PIID and supplementary PIID.
Plain-English Summary
FAR 4.1602 tells agencies how to identify the Procurement Instrument Identification Number (PIID) and any supplementary PIID on solicitation, award, and related procurement documents. It covers solicitations and solicitation amendments, contracts and purchase orders, delivery and task orders, blanket purchase agreements (BPAs), basic agreements and basic ordering agreements (BOAs), orders placed against BOAs and BPAs, modifications to those actions, and the placement of PIIDs on paper or electronic forms. It also addresses what to do when a form does not have a dedicated field for the PIID and how to handle additional agency-specific identification information. The purpose is to ensure every procurement action can be uniquely traced, linked to related instruments, and managed consistently across systems and documents. In practice, this section is critical for contract administration, reporting, auditability, and avoiding confusion when multiple related instruments exist under the same acquisition. It also helps agencies maintain clean records in electronic procurement systems and ensures that modifications and amendments are tied to the correct base action.
Key Rules
Identify PIIDs on all actions
Agencies must include PIIDs for all related procurement actions covered by this section. The PIID is the core identifier used to track the instrument throughout its life cycle.
Solicitations and amendments
Every solicitation must have a PIID. If the solicitation is amended, the amendment must use a supplementary PIID together with the solicitation PIID so the amendment is clearly linked to the original solicitation.
Contracts and purchase orders
Contracts and purchase orders must be identified by their PIID. This applies to the award document itself and ensures the base contractual action is uniquely identifiable.
Orders under existing vehicles
Delivery and task orders placed under contracts such as IDIQs, MACs, GWACs, and MAS contracts must identify both the order PIID and the underlying contract PIID. This dual identification links the order to the correct parent vehicle.
BPAs and BOAs
Blanket purchase agreements, basic agreements, and basic ordering agreements must be identified by PIID. Orders against BOAs or BPAs must identify both the order PIID and the PIID of the agreement; for BPA orders under a MAS contract, the order must also identify the MAS contract PIID.
Modifications need supplementary PIIDs
Modifications to contracts, orders, and agreements covered by this section must use a supplementary PIID, in accordance with agency procedures, and that supplementary PIID must be shown with the PIID of the instrument being modified.
Use agency procedures for forms
If a form or electronic format does not have a field for the PIID or supplementary PIID, the PIID must still be identified according to agency procedures. The absence of a field does not remove the requirement.
Separate extra agency identifiers
If an agency requires additional administrative identification information, that information must be clearly separated from the PIID so it is not confused with the official procurement identifier.
Responsibilities
Agency
Ensure procurement documents and electronic formats include PIIDs and supplementary PIIDs as required for solicitations, amendments, contracts, purchase orders, orders, BPAs, BOAs, and modifications. Establish procedures for placing PIIDs on forms that lack dedicated fields and for separating any additional agency-specific identifiers from the PIID.
Contracting Officer
Assign and include the correct PIID or supplementary PIID on the applicable procurement instrument and ensure related actions are properly linked to the base solicitation, contract, order, or agreement. Follow agency procedures when the form layout does not provide a PIID field.
Contractor
Review award and modification documents to confirm the correct instrument identifiers are shown and use those identifiers in performance, invoicing, correspondence, and recordkeeping as required by the contract and agency procedures.
Procurement/Contract Administration Staff
Maintain accurate document control and records by ensuring amendments, orders, and modifications are associated with the correct PIID hierarchy and that any additional administrative identifiers are kept distinct from the PIID.
Practical Implications
This section is mainly about traceability: every related procurement action must be tied back to the right base instrument, which reduces errors in administration, reporting, and audits.
A common pitfall is listing only the order PIID and forgetting the parent contract, BPA, BOA, or MAS PIID when the rule requires both or all three identifiers.
Another frequent issue is mishandling amendments and modifications by using the base PIID alone instead of a supplementary PIID, which can make it harder to distinguish the change from the original action.
When using electronic systems or preprinted forms, agencies still have to capture the PIID somehow; missing fields are not a valid excuse for omitting the identifier.
Contractors should verify that award documents and modifications reference the correct parent instrument, especially in IDIQ, GWAC, MAC, MAS, BPA, and BOA environments where multiple related instruments can be easy to confuse.
Official Regulatory Text
(a) Identifying the PIID in solicitation and contract award documentation (including forms and electronic generated formats). Agencies shall include all PIIDs for all related procurement actions as identified in paragraphs (a)(1) through (5) of this section. (1) Solicitation . Identify the PIID for all solicitations. For amendments to solicitations, identify a supplementary PIID, in conjunction with the PIID for the solicitation. (2) Contracts and purchase orders . Identify the PIID for contracts and purchase orders. (3) Delivery and task orders. For delivery and task orders placed by an agency under a contract ( e.g. , indefinite delivery indefinite quantity (IDIQ) contracts, multi-agency contracts (MAC), Governmentwide acquisition contracts (GWACs), or Multiple Award Schedule (MAS) contracts), identify the PIID for the delivery and task order and the PIID for the contract. (4) Blanket purchase agreements and basic ordering agreements. Identify the PIID for blanket purchase agreements issued in accordance with 13.303 , and for basic agreements and basic ordering agreements issued in accordance with subpart 16.7 . For blanket purchase agreements issued in accordance with subpart 8.4 under a MAS contract, identify the PIID for the blanket purchase agreement and the PIID for the MAS contract. (i) Orders . For orders against basic ordering agreements or blanket purchase agreements issued in accordance with 13.303 , identify the PIID for the order and the PIID for the blanket purchase agreement or basic ordering agreement. (ii) Orders under subpart 8.4 . For orders against a blanket purchase agreement established under a MAS contract, identify the PIID for the order, the PIID for the blanket purchase agreement, and the PIID for the MAS contract. (5) Modifications. For modifications to actions described in paragraphs (a)(2) through (4) of this section, and in accordance with agency procedures, identify a supplementary PIID for the modification in conjunction with the PIID for the contract, order, or agreement being modified. (b) Placement of the PIID on forms. When the form (including electronic generated format) does not provide spaces or fields for the PIID or supplementary PIID required in paragraph (a) of this section, identify the PIID in accordance with agency procedures. (c) Additional agency specific identification information. If agency procedures require additional identification information in solicitations, contracts, or other related procurement instruments for administrative purposes, separate and clearly identify the additional information from the PIID.