How to Recover Payment for Additional Work Under a Contract For Work and Services?

General Rules for Payment of Additional Work Under the Law

The Civil Code of the Russian Federation establishes that a contractor is not entitled to unilaterally increase the contract price. If the original price of the work is fixed, it cannot be changed without the parties’ mutual agreement, even if the actual scope of work turns out to be greater than expected. In the case of an estimated (non-fixed) price, the contractor must promptly notify the client of the need for additional work and agree on new terms.

Special rules apply to construction contracts. According to paragraph 3 of Article 743 of the Civil Code of the Russian Federation, if during construction it is discovered that certain work not included in the technical documentation is required, the contractor must inform the client and conclude an additional agreement regarding the performance and payment of such work. If the contractor fails to fulfill this obligation (by not notifying the client and not executing an additional agreement), they lose the right to demand payment for such additional work, as well as compensation for any losses incurred as a result of performing it.

The only exception is situations requiring immediate action in the client’s interest (for example, to prevent damage or destruction of the structure). In such cases, the contractor may claim payment for the urgent measures taken but must prove that the work was indeed necessary and could not be delayed.

Agreement and Documentation of Additional Work

To ensure payment, any additional work must be agreed upon with the client before it is performed. In practice, this means executing an additional agreement to the contract for work and services that specifies the new tasks and their cost. The additional agreement is signed by both parties and is usually accompanied by an updated estimate or a revised technical specification. Such an amendment to the contract establishes the client’s obligation to pay for the increased scope of work.

In certain cases, the law allows a notification-based procedure. In construction contracts, if the contractor notifies the client of the need for additional work and the client does not respond within ten days, the contractor has the right to suspend the work. The downtime caused by the client’s failure to respond is subsequently compensated if the additional work was indeed necessary. However, if the contractor ignores the lack of response and continues construction without a formal agreement, obtaining payment beyond the agreed price later will be extremely difficult.

Procedure for Documenting Additional Work

It is also important to comply with the form of agreement required by the contract. If the main contract was concluded in writing, the consent to perform additional work must also be in writing (a simple oral agreement has no legal effect). Otherwise, the contractor who fails to properly document the change in price and scope of work will be forced to perform the additional work within the original contract price — effectively at their own expense.

Finally, special attention should be paid to state and municipal contracts. In the field of public procurement, there are strict limitations on modifying the contract price: as a rule, the cost can be increased by no more than 10%, and only in compliance with specific procedures (Article 95 of the Law on the Contract System). Without formally amending the original contract price, additional work does not create an obligation for the contracting authority to pay for it, as doing so would violate public interest principles.

A contractor under a state or municipal contract is not entitled to recover payment from the budget for work performed without the client’s consent and in violation of the prescribed procedural requirements. Therefore, when working with public clients, all additional work must be documented with particular care through an official amendment to the contract.

Recovery of Payment in the Absence of an Additional Agreement

What should you do if additional work has already been completed, but the client refuses to pay, referring to the absence of an additional agreement? Court practice shows that, in some cases, contractors manage to recover payment for unsigned additional work if there is evidence that the client agreed to it. In other words, courts may side with the contractor under certain circumstances.

First, indirect evidence of the client’s consent. If correspondence (by mail or email) clearly confirms that the client approved the performance of the additional work, the court will take this into account. Similarly, minutes of working meetings attended by the client’s representatives, where the decision to perform additional work was made, can confirm that the client was aware and did not object.

Second, the signing of acceptance certificates and the subsequent conduct of the parties. There are cases where the client effectively accepted the result of the additional work and used it. If one party performed work without a formal agreement and the other party accepted the result, it is considered that the parties concluded an implied agreement for the performance of that work. The obligations arising from such an implied agreement are equivalent to those under a formal contract for work and services. In other words, the client’s acceptance of the additional work result may be interpreted as implicit consent to pay for it.

For example, in its ruling dated 29 September 2023, the Arbitration Court of the Ural District ordered the recovery of payment for additional work despite the absence of a signed supplementary agreement. The court determined that the parties had in fact acted in accordance with the draft agreement’s terms; the client accepted the work and did not deny that the scope and price had been coordinated in the course of project implementation. The court regarded such behavior by the client as confirmation that the contract had been effectively amended, despite the lack of a formal signature on the supplementary agreement.

Third, incorrect classification of work as “additional.” Not all work performed beyond the estimate is legally considered additional. If the disputed work essentially falls within the main scope provided for by the project documentation but was omitted from the estimate by mistake, it cannot be treated as “additional” under the law. In this case, the client must pay for it regardless of any special agreement. For instance, if the construction of a house initially included certain stages essential for project completion (for example, foundation waterproofing), but these stages were not listed separately in the estimate, the performed waterproofing work must be paid for as part of the main construction contract. Courts in such cases tend to side with the contractor.

Fourth, urgent and necessary work. If failure to perform unforeseen work could have led to project disruption or damage to already completed structures, the court may find the contractor’s claim for payment justified. Judicial practice has established this criterion: if the additional work was urgent and essential to ensure the suitability of the result, the absence of a supplementary agreement does not deprive the contractor of the right to payment. However, the contractor must prove the necessity of the emergency measures—typically through expert reports or records documenting defects that required immediate correction.

In summary, the chances of recovering payment for additional work without a formal agreement increase if the contractor can demonstrate that the client effectively agreed to it or that the work was objectively necessary. In any case, before filing a lawsuit, it is advisable to gather the most comprehensive set of evidence possible: letters, requests, acceptance certificates, photographs, witness statements—everything that confirms either the client’s consent or the objective necessity of the additional work.

If you are facing a similar situation, we recommend seeking an initial consultation with the legal team at KDpartners. Our specialists have extensive practical experience in handling contract disputes. We conduct legal assessments, assist in forming the evidentiary base, and ensure the protection of our clients’ interests both in pre-trial proceedings and in arbitration litigation.