Almost half of all savers say they would be more comfortable investing in pensions and the stock market if they had some form of guarantee.
A MetLife survey suggests 47% of savers would feel more secure with riskier types of investment if they knew they would at least get their original investment back.
Demand for guarantees has climbed through the year, according to MetLife, with just 41% saying they wanted such guarantees in May.
Dominic Grinstead, managing director of MetLife UK, says: "Fear of losing money when investing has always been one of the major motivations for savers and recent events have emphasised the risks.
"However stock market investing remains the best way to secure long-term returns despite volatility and the risks of short-term downturns. Investment guarantees remove the fear of losing your original investment while also offering the chance to lock-in gains.
Aviva says it has seen similar trends among its own customers, and is about to launch a guarantee option for its with-profits fund in response to demand.
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