§ Mr. Byers
To ask the Chancellor of the Exchequer what the cost to the Exchequer would be of allowing a married person to transfer their personal tax allowance to their earning spouse if they have(a) a child aged between six months and one year and (b) a child aged between one year and two years. 
§ Dawn Primarolo
[holding answer 23 March 2004]: The cost to the Exchequer through lower income tax of allowing married persons with children to transfer their full personal allowance to their spouse if he or she has a higher gross income for the two options are listed below.
Cost in 2004–05 per annum £ million Option a) married and with at least one child aged between 6 months and one year 160 b)married and with at least one child aged between one year and two years 340
Note:Figures rounded to the nearest £10 million. They exclude any estimate of behavioural response to the tax change.
The change in revenue for other taxes can only be provided at a disproportionate cost.