It's thought some motorists could be driving using provisional licences for almost 30 years.
Up to 30,000 are on their third or subsequent learners' permit and have never sat a driving test.
The figures from the Road Safety Authority, reported in the Irish Times, cover the period 1994 to now.
Transport commentator Conor Faughnan, says someone can continues driving without a full licence as long as they have a test booked:
"They are 'no shows' for the test itself to everybody's frustration, and they motor on without ever having done it. And they estimate that there might be over 600 people who've been in that situation since 1994 or earlier, which seems truly ridiculous. You could ask yourself why these people don't just go ahead and do the test and regularise it".
