However, there are some advantages to holding Canadian dividend paying stocks (and not just mortgage investment corporations, whose dividends are full taxable, like interest income) in TFSAs, RRSPs, or RRIFs, because one avoids the gross-up for div. tax credit purposes. That gross-up can push some senior citizens over the threshold for OAS claw-back, but in a tax sheltered account, one avoids avoids that problem altogether.