Life insurance has been placed sixth on a list of signs becoming an adult, being seen as a sign of becoming an adult by 21% of respondents to a survey for Beagle Street.
The research also found that the average age for feeling that you've become a grown-up is 29, although in some parts of the UK this was later.
In Norwich respondents felt like an adult at 31 and three months, while those in Brighton felt like an adult at the age of 31.
The most commonly named sign of becoming an adult was buying a first home, which signified becoming an adult for 64% of the 2000 adults surveyed.
Becoming a parent was cited by 63% of those surveyed as a sign of becoming an adult.
Getting married came third being cited by 52% of respondents, paying into a pension was cited by 29% coming forth and becoming house proud was rated fifth.
Reasons for not feeling an adult included relying on parents, named by 42%, and living at home longer, cited by 36% of those surveyed.
Matthew Gledhill, managing director of Beagle Street, said: "The research shows that growing up is less about years and more about reaching milestones in life like getting married, becoming a parent or buying a home.
"With each of these life events there is a need to take responsibility and a need to become an adult as you have people depending on you to do so."