In June and July, the number of the jobless was below 300,000.
A total of 23,906 reported to the HZZ in August, up 25.4% on the year, while 10,987 found jobs.
The City of Zagreb accounted for the most jobless - 40,500 - or 13.4% of the total number.
Also, 22.1% of the jobless registered with the HZZ received unemployment benefits, up 2% from August 2011.