Child and Family Agency Tusla has apologised to applicants who are waiting for their birth and early years information and those seeking to trace a relative.
The Birth Information and Tracing legislation was enacted and commenced in July last year, while the service began in October.
The act was passed to provide people access to birth certificates, birth and early life information for people who were adopted, boarded out, the subject of an illegal birth registration or who otherwise have questions in relation to their origins.
However, Tusla has confirmed that a backlog of applications received in the initial three months will not be cleared until the end of July.
The agency has had to "significantly scale up" the service with additional staff to minimise the delays experienced by applicants.
The latest figures show that as of last Monday, 13 February, Tusla had received 7,032 applications since the service launched last year.
While it has welcomed the high level of interest from people seeking their information within the provisions of the new act, Tusla has said that it had not fully anticipated the significant volume of applications that would be received within the initial eight-week period.
In line with the act, applications are categorised into 30-day or 90-day response categories, depending on the complexity of the task involved in retrieving the relevant records according to the Child and Family Agency.
"As information applications have been screened, it has become evident that most of the applications to Tusla fall within the 90-day category," according to the agency.
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People seeking information can apply to the Adoption Authority of Ireland and Tusla for their records.
The majority of people have requested documents from both bodies.
By last Monday there were 2,811 applications to the Adoption Authority of Ireland.
The number of completed cases by the AAI were 877.
Tusla has said that the records it holds are historical, vary in format and condition and not all are digitised, so the process can involve manual searching and extraction of records across different databases, or locations.
It has said that the initial application surge and the number of applications categorised as complex in line with the act, has resulted in "a significant delay in responding to applicants, within the statutory response times".
As a result, Tusla has significantly scaled up this service with additional staff to minimise the delays experienced by applicants.
The agency confirmed it expects to clear the backlog of applications received in the initial three months of operation by the end of July 2023.
However, it has said that many applicants "will receive their information sooner", as applications are being processed and issued every week.
As of last Monday, Tusla had processed and issued 1,043 requests for information, with more due for completion and issue each day.
"We are in the process of notifying every person that has applied for their information, to inform them of the date they can now expect to receive their information," it said.
"We are very aware of the disappointment and upset this is causing for so many people who have been waiting a long time for their information, and for this, we sincerely apologise.
"We would like to sincerely thank those people who have received their information and have contacted our staff to acknowledge the quality of the information released to them by Tusla in line with the new legislation."
Contact the Tusla Birth Information and Tracing Team at 0818 44 55 00 between 10am and 3pm Monday to Friday, or by email birthinfo@tusla.ie or BITCounselling@tusla.ie for support and counselling.