Redundancies are running 10.9 per cent ahead of last year, with job losses in the construction, manufacturing and services sectors driving the increase.
The latest figures from the Department of Enterprise, Trade and Employment show that 1,866 redundancies were reported last month, 17.3 per cent ahead of the same month in 2006.
The September total brings the number of redundancies reported so far this year to 19,218.
At the same stage in 2006, the total was 17,324. For last year as a whole, 23,684 redundancies were recorded.
The annual increase is among the highest recorded for any month this year.
September saw a number of high-profile redundancy announcements, including the loss of 256 jobs at Coca-Cola in Dundalk, Co Louth.
A breakdown of the Department's figures shows that the largest number of notifications in September - 632, or a third of the total - came under the "other services" heading.
The second-largest contribution to the total came from "other manufacturing", with 478 notifications. This was followed by 365 redundancies in building and civil engineering firms.
Males outnumbered females almost by two to one in the total number of redundancies for September, accounting for almost all the redundancies in the construction and engineering sector.
A sectoral breakdown for the year to date shows that the services sector also provided about a third of the total for the first nine months.