The ONS estimates one in five people now aged 18 to 74 suffered or witnessed at least one form of emotional, physical and sexual abuse before the age of 16.
The survey also estimates that around one in 13 adults aged 18 to 74 were victims of sexual abuse before the age of 16 and four in 10 victims of child abuse experienced more than one type of abuse.
The data was compiled by the Department for Education (DfE), National Association for People Abused in Childhood (NAPAC), National Society for the Prevention of Cruelty to Children (NSPCC) and the Welsh government.
Megan Elkin, head of the ONS centre for crime and justice, said “measuring the scale of child abuse is difficult as it often remains hidden”.
“In the year ending March 2019, the police in England and Wales recorded 73,260 sexual offences where it is known the victim was a child. However, the numbers relate to offences rather than children – one child could be the victim of multiple offences,” she added.
The findings on adults experiencing abuse as children were compiled using data from the Crime Survey for England and Wales (CSEW).
However, the CSEW underestimates the total number of adults who were abused as children because it does not count abuse against 16- and 17-year-olds.
In addition to gaps in police and CSEW records, just one in four adults had reported their abuse to police, the ONS estimates.
Some 14 per cent of adults who contacted NAPAC last year had never told anyone about the abuse previously.
The ONS also analysed DfE and Welsh Government data showing how many children had been referred to local authority children's services due to abuse or neglect.
On 31 March 2019, 49,570 children in England were looked after by their local authority because of abuse or neglect while 52,260 children in England were the subject of a Child Protection Order.
A further 4,810 children in Wales were looked after because of abuse or neglect.
The number of children looked after because of abuse or neglect has increased by four per cent in England and by six per cent in Wales in the last recorded year, figures show.
Imran Hussain, Action for Children’s director of policy and campaigns, said: “Young people suffering from abuse must be able to access the help they need as soon as possible - not only to stop the abuse in its tracks but also to deal with the impacts before they lead to a lifetime overshadowed by crisis. The new government must bring in a National Childhood Strategy, with proper funding for children’s services, to give all children the chance at a safe and happy childhood.”