User acceptance testing (UAT) is significant in software development as it ensures that the system meets user requirements and expectations before final deployment. This phase allows real users to validate the software's functionality, identifying any issues or discrepancies early on, thus minimizing the risk of costly post-launch fixes. UAT emphasizes the user experience, ensuring that the software is intuitive and meets intended goals. Through this iterative feedback loop, development teams can make necessary adjustments, enhancing overall quality and increasing user satisfaction.