The HMRC (Her Majesty's Revenue and Customs) has confirmed new advisory fuel rates for diesel vehicles, which will take effect on June 1, 2026. The updated rates include a 15p per mile charge for diesel cars with engine sizes of 1600cc or less, while those with engines ranging from 1601cc to 2000cc will incur a 17p per mile charge. The highest rate of 23p per mile applies to diesel cars with engines exceeding 2000cc. These Advisory Fuel Rates (AFRs) are crucial for company car drivers, as they help determine how much fuel expenses can be claimed back from employers. HMRC issues these rates quarterly, allowing for timely adjustments in response to fluctuating fuel prices. It's important for drivers to adhere to these rates to avoid any taxable profit or National Insurance liabilities. If reimbursements exceed the AFRs without appropriate documentation of higher fuel costs, the excess will be treated as taxable profit.