Single people, along with those who have children under the age of 18, are less likely to have drawn up a will than their counterparts who are or have been married.
This is according to Standard Life, which also found that, despite the ongoing credit crunch, 22 per cent of people plan to leave money to charity in their will.
In addition, the firm discovered that 64 per cent of consumers questioned were unaware that inheritance tax exemptions exist for gifts made from left over income.
"Making a will and keeping it up-to-date can save family and friends a great deal of distress and potentially money, so it should be regarded as a priority," advised Julie Hutchison, head of estate planning at Standard Life.
She added that is it "particularly concerning" that single people are more likely not to have made a will.
Figures cited in a recent BBC report suggested that an estimated one in six UK couples cohabit without having their relationship legally formalised, which could lead to complications when people die intestate.