Motor tax is payable on an annual, half-yearly or quarterly basis. The rates of duty applicable for half yearly and quarterly options are 55.5% and 28.25% of the annual charge respectively. This additional cost element takes account of the extra workload for staff in motor tax offices and the National Vehicle and Driver File unit, and the resultant administrative costs and printing costs that arise, including the issuing of renewal notices.
The estimated annual income from the increased charges for half-yearly and quarterly vehicle licences is in the region of €50m. A loss in income from this source would have a negative impact on revenue and would have to be borne elsewhere in the motor tax system or through the taxation system generally.
I have no plans to adjust the basis for paying motor tax on a half-yearly or quarterly basis currently.