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HMRC internal manual

Capital Allowances Manual

RDA: Outline

RDA is the allowance formerly known as scientific research allowance. FA2000 changed the name but the scope remains the same. RDA gives relief for capital expenditure on research and development incurred by a trader. Allowances are only due if the research and development is related to the trade that the trader carries on. The expenditure on which allowances are given is called qualifying expenditure CA60400.The allowances are very generous because the rate is 100%. There is a balancing charge if an asset representing qualifying expenditure is sold, demolished or destroyed but there is no balancing charge if the use of the asset changes CA60500.

RDA is only available to traders. A person carrying on a profession or vocation is not entitled to them.