As most Canadians in their early earnings years are not earning high incomes, their marginal tax rate is low, so the tax deduction that RRSPs provide has low utility, plus RRSP contributions are locked in as withdrawals mean higher income taxes in the year of withdrawal. Not only that, but the inflation rate is such that the real value of the original investments drops year after year, RRSP investments cannot be used as collateral, and the management expense ratios will help wipe out the real earnings of your fund. Perhaps in the high earning years of a professional, for example, the RRSP tax deduction makes sense, providing one's heath is such that one can reasonably expect to withdraw from one's RRIF. Given the TSIF contribution limits, which increase by the year, for many people their savings might not be enough to surpass the limit, and until they do, when you put money into an RRSP you lose control over your finances, and if your tax rate is high, the trade-off might work for you.