The article examines the relation between the actual reimbursement of legal aid costs and the actual costs in civil proceedings. The case law is analyzed in the part of documentary confirmation of the expenses incurred in the case of expenses for the assistance of a professional lawyer, as well as the possibility of considering the issue of changing the costs of professional legal assistance at the request of a party or in the absence of a corresponding request of a party. Procedural Code of Ukraine does not specify a clear list of documents that a party must submit to confirm the costs incurred by it in the case of expenses for professional legal assistance, but the most common practice is the signing of an act of work performed by a lawyer and a client, in the absence of such a document, the courts refuse to compensate for costs parties to professional legal assistance. The practice of national courts regarding the confirmation of incurred expenses for professional legal assistance is heterogeneous, in this connection lawyers have to sign with clients all possible documents for the confirmation of the rendered services in order to prevent a court refusal to reimburse such expenses. The author emphasizes that the absence of a unified position of the Supreme Court, even at the level of the united chamber of the Court of Cassation concerning the different approach concerning the possibility of considering the reduction of the costs of professional legal assistance at the request of a party or in the absence of a corresponding request of a party may continue to give rise to the right.