It is the responsibility of the EU Member State where the unaccompanied child resides to identify those children who would be eligible for transfer to another Member State under the Dublin III Regulation. The Home Office does not have access to the personal details of all unaccompanied children present in other EU Member States.
The Home Office publishes annual data on the Dublin III Regulation in the Immigration Statistics. This includes data on the number of requests to transfer into and out of the UK and the number acceptances and transfers into and out of, broken down by article and Member State requesting. The latest data, covering up to 2019, can be found at:
Instructions on how to use the data can be found in the ‘Notes’ sheet.