Income is classified under a number of categories for taxation purposes and there are distinct rules for each category. As the Deputy notes, rental income from Irish property is taxed under Case V of Schedule D. The rules for Case V provide that landlords can carry forward rental losses for offset against future rental profits, but cannot offset rental losses against other net taxable income in the current year, other than rental profits from other Irish properties. Revenue have informed me that the manner in which losses are recorded on tax returns reflects the current structure of tax legislation, that is, Irish rental losses can only be offset against profits from Irish rental properties. As such, given the data which is available, it is not possible for Revenue to estimate the cost of allowing rental losses to be offset against non-rental profits.