Contract Amendment in Procurement Law 2026

Definition: A contract amendment (Nachtrag) is a modification or extension of the contract content agreed after the conclusion of the contract, which is due either to changed circumstances, to additional performance requirements of the contracting authority, or to gaps in the original bill of quantities, and whose admissibility under procurement law depends on the limits of § 132 GWB (Art. 72 Directive 2014/24/EU).

Last updated: January 2026 · Legal basis: § 132 GWB, Art. 72 Directive 2014/24/EU, § 2(3) VOB/B, § 382 BVergG 2018

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What is a contract amendment in procurement law?

A contract amendment refers to the mutually agreed modification of a public contract already concluded, which modifies the originally agreed scope of performance, the price, or other essential contractual terms. Amendments are particularly common in the construction industry, since deviations from the originally planned performance regularly occur in the course of execution. Procurement law sets narrow limits to amendment practice in order to prevent contractual adjustments after the event from circumventing competition.

Admissibility of amendments under procurement law

The central procurement-law question regarding an amendment is: does it constitute a permissible change to the existing contract or a new performance subject to a tender obligation? Art. 72 of Directive 2014/24/EU (transposed in § 132 GWB) lays down exhaustively the conditions under which an ongoing contract may be amended without a new tender procedure.

Permissible amendments without a new tender procedure:

1. Review clause: The original contract contained a clear, precise and unambiguous review clause
2. Additional performance: Necessary additional performance that was not part of the original contract, whose contract value does not exceed 50 % of the original contract value, and which cannot be separated from the main contract without significant inconvenience or additional costs
3. Unforeseeable circumstances: Modification due to circumstances which a diligent contracting authority could not have foreseen, provided that the overall character of the contract is not altered and the value increase does not exceed 50 % of the original contract value
4. Minor modifications: Modifications whose value does not exceed 10 % of the original contract value (15 % for works) and that do not alter the overall character of the contract
5. Change of contractor: Under narrowly defined conditions (e.g. corporate restructuring)

Contract amendment and VOB/B

In the construction sector, the VOB/B and the BGB govern the relationship between contracting authority and contractor in case of subsequent changes to performance. Under § 1(3) and (4) VOB/B, the contracting authority can order modifications to the building design or additional performance; the contractor is then entitled to reasonable remuneration under § 2(5) and (6) VOB/B. The procurement-law limits of § 132 GWB must always be observed.

Consequences of inadmissible amendments

An amendment that is inadmissible under procurement law qualifies as a de facto award and can lead to the nullity of the contract; moreover, ex officio review by the review bodies and possible recovery in EU co-financed projects loom. Contracting authorities should therefore always check, before concluding an amendment, whether it falls within the permissible limits.

Austria: Contract amendments under BVergG 2018

In Austria, § 382 BVergG 2018 governs the conditions for amending ongoing contracts and corresponds in substance to Art. 72 of Directive 2014/24/EU. The Federal Procurement Review Authority and the Federal Administrative Court have developed an extensive body of case law on the admissibility of amendment agreements.

FAQ

From what point is an amendment problematic under procurement law? As soon as it alters the overall character of the contract, fundamentally changes essential terms, or exceeds the percentage thresholds (10/15/50 %), a new tender obligation generally arises.

Must an amendment be agreed in writing? Procurement law does not prescribe a particular form, but written form is always advisable for documentation reasons. In the construction sector, the written form is customary under VOB/B and BGB works-contract law.

What is the difference between an amendment and amendment management? The amendment is the individual contractual modification; amendment management refers to the systematic process of identifying, documenting and handling amendments over the project's duration.

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Last updated: January 2026 All information without guarantee. For legally binding advice, please contact a law firm specialising in procurement law.