The subject of the article is an analysis of the legal consequences of a preliminary payment reservation in developer contracts. The paper discusses legal consequences of establishing a down-payment in the event of non-performance of a developer contract by one of the parties due to circumstances for which this party is solely responsible, including the relation between Article 394 of the Civil Code and Article 29 of the Act on the Protection of the Rights of Buyers of a Dwelling or a Single-family House as the legal basis for withdrawing from the contract, the problem of admissibility of withdrawal without setting an additional deadline and the issue of supplementary compensation exceeding the value of the subject of the preliminary payment or twice the amount. The legal consequences of a preliminary payment in the event of performance of a developer contract, its termination and non-performance due to circumstances for which neither party is responsible or for which both parties are responsible are also presented.