Four in ten parents with children under the age of 18 do not have any life insurance, a survey for Sainsbury's Bank Life Insurance has found.
The majority, about two thirds, do not have any critical illness protection, the survey of 2,002 UK adults carried out by Opinium Research found.
Among those parents without life insurance, 49% say they cannot afford it, while 21% do not believe it is necessary.
Over one in ten parents, 14% said they planned to take out life insurance but had not got around to it, while 7% said they had formerly had cover but could no longer afford it.
About a third (36%) said they had never reviewed their cover, while 10% had increased their life insurance cover as they had children.
Research for SoSmart Money found that those aged 55-64 are most likely to believe life insurance is unimportant, with 18-24 year olds most likely to believe it is important.
Scott Gorman, Head of Sainsbury's Life Insurance said: "Life insurance is an important financial safety net and should not be overlooked.
"Families should consider life insurance with critical illness protection as early as possible to cover their mortgage, any borrowing and other day-to-day commitments to ensure financial stability, if the worst happens."
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