There were 360 incidents of children going missing from State care last year, with almost half in private residential centres.
Figures released by Tusla under Freedom of Information show that the longest period a child was missing was almost three weeks.
According to the data, there were 360 instances reported of children absconding or going missing from a variety of care settings in 2020, although it said there may have been some duplication as a result of children transferring from one sector to another, meaning a slightly lower figure of 319 distinct incidents.
Of the cases reported, 169 took place in private residential care settings, with another 109 from voluntary care settings and 71 from Tusla statutory services.
There were 12 young people who went missing from special care centres, operated by Tusla.
The ages of those in the different residential care settings range from 11 to 17.
The longest time for which a child went missing was 19 days in private residential care, 18 days in special care, 11 days from Tusla statutory services and a week from voluntary care.
Tusla said all children and young people in residential care are required to have an Absence Management Plan, which aims to "ensure that children are given age-appropriate curfews/coming in times which reflect their ability to keep themselves safe when they are unsupervised with the community".
Under a joint protocol between Tusla and An Garda Siochána, gardaí must be notified by care staff that a child is missing once they have been away from their placement for longer than expected and Tusla and the child’s carers have made all reasonable efforts to locate them.
Once a child has been reported missing, the gardaí have primary responsibility for investigating the child’s whereabouts, although the child’s social worker and carers continue to make enquiries, with all information passed onto gardaí.
A recently-published report by health watchdog Hiqa said: "While absconding from their care placement is not an unusual behaviour for some children, these occurrences brought particular challenges in relation to infection prevention and control.
"Our inspections found that some children continued to abscond during the pandemic and that necessary adjustments were being made to receiving a child back into a centre on their return from an abscond."
"The use of restrictive practices were well monitored and reviewed by centre managers for their effectiveness, necessity and proportionality."
Hiqa said within a 16-week period between February and June last year, it twice inspected a special care unit in response to the volume and nature of notifications of absconsions.
"In relation to absconsions, the systems in place to ensure outings from the centre were safe, purposeful and resourced adequately were not strong enough.
"Similarly, decision-making processes to respond to absconsions, particularly established patterns of absconding behaviour by individual children, needed to improve significantly."