I am informed by the Revenue Commissioners that the full year cost to the Exchequer, estimated by reference to 2013 incomes, of increasing the standard rate band for single income married couples and one parent families to the threshold of €65,600 which currently operates for dual income married couples, would be approximately €695 million. However, given the current band structures, major issues would need to be resolved as to how in practice such standard rate band changes could be integrated into the current system and how this would affect the relative position of different types of income earners.
This figure is an estimate from the Revenue tax-forecasting model using actual data for the year 2010 adjusted as necessary for income and employment trends in the interim. It is, therefore, provisional and likely to be revised.