Simplifying the formal structure of UK income tax

The tax system in the UK has developed through numerous ad hoc changes to its structure. This has resulted in a situation where the way in which the tax system is described does not readily correspond to the marginal rate schedule actually faced by taxpayers. This paper outlines the connection between the formal description of the tax system and the marginal rate schedule faced by taxpayers. It argues that the operation of the tax system would be greatly clarified if it were described explicitly in terms of its marginal rate schedule.