Section 23(1)(b) in The Chennai Metropolitan Water Supply and Sewerage Board's Water Tax and Sewerage Tax (Levy and Collection) Regulations, 1991
(b)If such date falls within the last two months of the half year, the owner shall, subject to the notice being given in sub-clause (a) of clause (1) be entitled to remission of the whole of the tax or enhanced tax, as the case may be payable in respect of the building only for that half year.