A third of children between the ages of eight and 17 with a social media profile have lied about their date of birth, according to new research by Ofcom.
Youngsters do so in order to appear they are over 18, says the Government backed regulator.
The suvey’s results come at a time when there is a clamour for age verification tools to protect children from harmful content.
Ofcom found that 77% of children in the surveyed age range have at least one social media profile, with 60% of those under 12 having one despite most sites having a minimum age requirement of 13.
Research showed around 47% of children in this group set their age at 16 or over, while 32% had set it at 18 or over.
Within that group, the study said around 23% of those between eight and 12 had a profile with an age set at 18, exposing them to material aimed at adults.
The Online Safety Bill is due to be brought back to parliament soon.
The bill would compel platforms to protect users, particularly children, from illegal, dangerous and harmful content, with large fines and possible blocks on sites that breach the rules.
Some platforms, such as porn sites, may also have to use age verification methods to prevent children from accessing content.
Mark Bunting, director for online policy at Ofcom, told Sky News: “The protection of children sits at the core of the new online safety laws, so as we prepare for our new responsibilities we’re continuing to build our evidence of children’s lived online experiences.
“Today’s research explores the triggers that may lead children to experience harm online, including the risks of signing up to a social media platform with a false older age. This can put them at greater risk of seeing potentially harmful, age-inappropriate content.
“The children and parents in the study spoke of the potential tensions between online safety concerns and the need for greater protection, with the desire for youngsters to feel socially included and to have freedom to learn how to manage risks through experience.”