Americans still plan for their estate and financial legacy by the seat of their pants, a new study says.

More than half of Americans don’t even have a formal estate plan, and those who do often fail to talk about their plans with their families, according to a survey from Chicago-based BMO Wealth Management.

The the survey report released this week found that 52 percent of Americans do not have a will in place.

BMO found that most respondents planned to leave each of their heirs equal portions of their assets, and that spouses and children were most often indicated as heirs. Yet some planned to distribute their estate unequally (between 5 percent and 15 percent, depending on marital status) or not leave an inheritance at all (between 7 percent and 20 percent).

BMO believes such plans could cause division within families if not properly communicated to heirs ahead of a client’s death. Nevertheless, 40 percent of the survey’s respondents had not discussed their estate intentions with their children. Only one in three respondents said that their heirs were aware of the locations of estate planning documents such as a will or powers of attorney.

Only 28 percent of the respondents said that they had estate planning discussions with their parents. Perhaps as a result, 40 percent of those surveyed felt that the distribution of their parents’ estates was unfair.

BMO sponsored a survey of 1,008 Americans age 18 and older in December.