" My client had negative retained earnings (deficit) on the balance sheet, that should mean that he had non-capital loss, right?"
- Not necessarily - Could have been Capital Losses or something else
“However, why does rep a client doesn’t show the corporation had non-capital loss?”
- CRA has not implemented that online - and, there might not be any non-capital losses for the corporation…
“So if I file a return claiming the loss, will CRA accept it?”
- What loss are you referring to? You don’t have any non-capital losses according to your post.
“Is there a way I can find out how much loss was from which year?”
- By obtaining copies of the last 10+ years of the Corporations Financials, Tax returns, and assessments, or alternatively some reliable working paper schedules from the accountant who prepared the previous year
“the previous accountant just randomly put a number so it make the taxable income to 0”
- That potentially could be quite a serious matter, and should be investigated further to ensure that the Opening Balances are not false and misleading - also, if you have evidence it was “random” (and classified as what?), the prior year may need to be re-stated/re-assessed after correction…