Some 24% of people in the UK have been landed with a debt of £1,450 within a week of the death of a loved one.
Four out of five of those who faced such a debt were unaware their family member owed any money, according to the research by funeral plan provider Perfectchoicefunerals.com.
While 64% discovered the debt in the first week, a further 10% said it took more than a year for the debt to come to light.
The study, which looked at bereavements over the past five years, found that of the debts inherited (excluding mortgages), 61% were from credit cards and 54% came from bank loans. A further 32% came from store cards, 25% from overdrafts and 18% from payday loans.
On average it took relatives seven months to repay the inherited debt, faced by 38% of partners, 21% of siblings and 15% of the deceased's children.
Don't hide debt
Emma Simpson of Perfectchoicefunerals.com said: "Whether expected or not, the death of a family member is usually an incredibly difficult time, so revealing any debts that might exist can be a difficult subject to handle on top of all the other emotions that the relatives are going through.
"Obviously, we strongly believe in planning for the future and including the subject of debt within that is important, to spare relatives more pain than they already have to go through."