Half of adults are not aware of power of attorney, which allows people to appoint someone to make decisions on their behalf if they lack the mental capacity to do so themselves.
The poll by Royal London found that of those who are aware of it, only one in three (30%) think they fully understand what it does.
Among adults who know of power of attorney, around three quarters (76%) are aware of a financial power of attorney but only around half (48%) are aware of a welfare power of attorney, which covers things like end of life health care decisions.
A quarter (23%) of women said they have discussed setting up a power of attorney compared to just one in six men (17%).
Men (18%) who haven’t discussed setting one up were more likely than women (8%) to say that they did not think they would ever need to set one up.
The study also found there was a lack of discussion on the subject, with almost half (48%) of adults not thinking they are at an age when they need to think about it, despite three in 10 (34%) being over 55.
One in five (19%) said the reason for not discussing it was because they did not want to think about being unable to manage their own affairs.
Mona Patel, consumer spokesperson for Royal London, said appointing a family member or trusted friend to make financial or welfare decisions on your behalf stops the responsibility falling to the state and loved ones then having to apply to the Court of Protection, which can be emotionally difficult, time consuming and expensive.