While all investments carry some level of risk, preference shares are generally considered less risky than common shares due to their fixed dividend payments and higher claim on assets in case of liquidation.

Additionally, cumulative preference shares offer the advantage of accumulating unpaid dividends, ensuring that you will receive any missed dividend payments in the future, further reducing investment risk. 

However, they are riskier than bonds as they do not have the same level of repayment guarantee, given that they are a type of equity.