This paper explores how blockchain technology can accelerate negotiations within industrial supply chains, focusing on prototype management in the automotive sector. Through a real case study involving a car manufacturer and a tier 1 supplier, we analyse the complex workflow from prototype request initiation to purchase order issuance. The study identifies critical bottlenecks that hinder process efficiency, such as communication delays and prolonged negotiations. By simulating blockchain-based transactions on the Ethereum platform, our analysis quantifies the costs associated with decentralised record-keeping and smart contract execution. The findings demonstrate that blockchain enhances transparency, traceability, and data integrity while reducing reliance on intermediaries and mitigating negotiation delays. Despite challenges such as cryptocurrency volatility and the need for operational adaptations, our results highlight blockchain’s potential to streamline supply chain interactions and lower overall transaction costs. This work contributes to the supply chain optimisation and digital transformation literature by providing empirical insights and practical guidelines for integrating blockchain solutions in complex industrial environments.