Respected sir, My client register in Gst from 01 Oct 2018 and he filled his Gst return nill so my query is can I show my income before 01 Oct 2018 in his income tax return. because after 01 Oct he filled his nill Gst return.
Whichever return is filled earlier, the turnover data for both i.e GST & IT should be identical; otherwise you will get query from either of department.
For the period upto your registration under GST, turnover should be authentic.