Irish Revenue has issued eBrief No. 187/23 concerning an update to the Tax and Duty Manual on Excise Duty Rates on Energy Products and Electricity. The Manual has been updated to reflect increases in the rates of Mineral Oil Tax (MOT) on certain mineral oils with effect from 1 September 2023. Increases in rates apply to petrol, auto-diesel, aviation gasoline, heavy oil used for air navigation and private pleasure navigation, and marked gas oil (MGO)/green diesel. The MOT rates for substitute fuels also increased from that date.