9A Computation of capital gains or losses derived from securities and book-entry securities (3064e)
Form for reporting capital gains or losses derived from stock-market trading or sales of securities, if this information is not already showing in the taxpayer's Pre-completed tax return form. Read the instructions carefully.
E-file - report your 2017 capital gains or losses
Tax Return on the Web (tax.fi/taxreturn)
If you e-file, there is no need to send back the paper-printed form.
If you use paper filing, send the form 9A as an enclosure to printed Pre-completed income tax return.