Starting a family, business or new job were also highlighted by the company, along with approaching retirement or moving to a larger home.
Bonnie Burns, Legal & General's protection product marketing director, said: "Protection insurance is typically seen as an afterthought when buying a house, but it is much more important than that.
"People may not realise that they could put their families under enormous financial pressure if they were to die or get ill because bills still need to be paid."
A recent study by the Co-operative Bank and Places for People found that many first-time buyers are sacrificing luxuries such as eating out and holidays to afford new homes.
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