Spreading the withdrawal of the Personal Allowance is the best value way to eliminate high marginal tax rates

Marginal Tax Rate vs Gross Income

In a model which adjusts for the labour response, this policy would cost £590m in 2029/30. Completely abolishing the withdrawal of Personal Allowance, would cost £6.5bn in 2029/30 (with the same model).
Chart: Centre for British ProgressSource: GOV.UKGet the dataCreated with Datawrapper