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HMRC internal manual

Oil Taxation Manual

Capital allowances: ring fence expenditure supplement: relevant percentage for calculating the supplement


The RFES is calculated as a percentage of the qualifying E & A (pre-commencement) expenditure or (post-commencement) losses at the relevant time. At introduction the rate of RFES (the ‘relevant percentage’) was 6% per annum. The rate increased to 10 percent for accounting periods beginning on or after 1 January 2012. The amount of supplement is proportionally reduced if the accounting period to which the claim relates is less than 12 months.