This case study presents the engineering, supply, integration and commissioning of ultrasonic custody transfer metering systems for Indian Oil Corporation Limited (IOCL) at Dahej Dispatch and Koyali Receipt Terminals. The turnkey scope included 10-inch and 12-inch ultrasonic metering skids, pressure reduction and filtration systems, slam shut-off and gas-over-oil actuated valves, instrumentation and SCADA integration. The project focused on accurate natural gas flow measurement, operational safety, compliance with IOCL specifications and reliable pipeline operations. It highlights the role of integrated metering and automation solutions in improving custody transfer measurement assurance.