The Junior Cert results will be published later than usual and on a Friday instead of midweek, the State Examinations Commission (SEC) has confirmed.
Pupils who sat their exams last June will now get their results on October 4.
It is about three weeks later than usual, because of the major overhaul to the Leaving Cert results and appeals process this year.
The Leaving Cert results were issued a day earlier and the appeals process has been shortened to allow for outcomes to be released in the week beginning September 16.
It emerged last week that the number of appeals had almost doubled this year, which has put further pressure on the SEC and led to a knock-on delay for the publication of the Junior Cert results.
Earlier this year, the SEC advised schools that it hoped to release Junior Cert results at the end of September, but that is now being pushed out further to the first week in October.
The National Association of Principals and Deputy Principals (NAPD) said it "acknowledges the understandable disappointment that students and parents may feel" by the delay.
However, the NAPD welcomed the news that the results will now be available on a Friday - rather than a Wednesday as is usual.
"Distributing results at the end of the school week will give students and schools additional time and space to assess their performance and allow teachers to give students any extra support they require," said NAPD director Clive Byrne.
"The NAPD is glad to see the prioritisation of the Leaving Certificate appeals process as the changes have gone some way in easing the stress placed on students as they seek to move on to third level."