Results published in the latest Australian Journal of Social Issues reveal while an estimated 87 per cent of Australian adults make gifts to charity each year, only 5.4 per cent of estates make provision for a post-mortem bequest to a charity.

Faculty of Business and Enterprise Research Fellow Christopher Baker said childless Australians were the most likely to donate in the event of their death, accounting for two-thirds of charitable bequests made through wills.

Unlike wealthy Americans, who are known for their conspicuous philanthropy, rich Australians leave a smaller proportion of their estates to charity than their poorer - or childless - counterparts.

''Despite the fact that most of us give regularly to charity throughout our lives, when it comes to our wills, we give it all to family,'' Dr Baker said.

''Most people tend to think that as Australians we are generous and respond well to people in times of flood, fire and other disasters, but only a small minority do so in their wills.''

Dr Baker said most Australian wills followed the same basic pattern.

''The records show that Australians overwhelmingly leave their estates to immediate family members - first spouses, then children,'' he said.

''They also show that there is a significant discrepancy between what people do with their estates and intestacy laws that determine how estates are distributed in the absence of a will.''