An average of 40 per cent of applications for passports in the system at any one time are incomplete and require further action by the applicant before they can be issued, according to the Department of Foreign Affairs.
The figure comes following the raising of concerns by TDs and others about delays in the issuing of passports.
There has been a surge in demand for passports as people seek to travel abroad now that the Covid-19 pandemic has receded.
The Passport Service has issued more than 460,000 passports since the beginning of this year, compared with 634,000 in total in 2021.
About 41,000 passport applications are being delayed because the applicant has not provided all of the required information or documents
The Department of Foreign Affairs said while the Passport Service “is experiencing a very high volume of applications, this does not represent a backlog”.
It said there is “a continuous stream of new applications and a continuous dispatch of completed passports happening every day”.
Some 45 per cent of adult renewal applications are processed within one to two days.
The average turnaround times for passports are 10 working days for Simple Adult online renewals and 30 working days for first-time applications.
Earlier this month Minister for Foreign Affairs Simon Coveney told the Dáil the service was experiencing high demand for first-time passports, particularly for children, with 88,000 such applications in the system.
On the proportion of incomplete applications Mr Coveney said every effort is made to contact the people involved but the experience of the Passport Service is that it can take weeks and sometimes months for applicants to send the necessary documents.
This means they cannot be processed within the average turnaround times.
The kinds of missing supporting documents can include witnessed identity forms or consent forms for children, birth certificates and other documents required to prove identity and entitlement to citizenship.
Mr Coveney provided figures on the number of passport applications, including those that were incomplete, for various counties in response to questions from TDs.
There were 3,693 applications on hand requiring further action in Cork, 1,740 in Kildare, 1,242 in Limerick, 1,127 in Wicklow and 1,017 in Tipperary – all about 40 per cent of the total applications in those counties.
The Department, in a statement, said a new system was put in place in early March that aims to improve the processing speed and turnaround times for such applicants. Once additional documents sought are received, “they are prioritised and where applications are complete, they can now be processed in 15 working days”.
“This significantly reduces the processing time, particularly for first time applicants,” it said.