Section 360J | Amount of allowance F1
From legislation.gov.uk
(1)The writing-down allowance for a chargeable period is 25% of the qualifying expenditure.
(2)The allowance is proportionately increased or reduced if the chargeable period is more or less than a year.
(3)The amount of the writing-down allowance for a chargeable period is limited to the residue of qualifying expenditure.
(4)For this purpose the residue is ascertained immediately before writing off the writing-down allowance at the end of the chargeable period.