This was the first time since October 2008 that numbers this low have been seen, the IEPF said.
Some 47,979 young people were out of work in October, which is 21.1 percent down on a year ago.
The number of long-term unemployed was 199,869 people in October, below 200,000 for the first time since the beginning of 2011, a 16.4 percent year-on-year decrease (39,116 fewer people) and 2.7 percent in monthly terms (5,456 fewer).
Unemployment decreased most in the Algarve (27.3 percent less).
Regarding the economic sectors, 69.4 percent of registered people in unemployment centres had worked in sectors such as services (69.4 percent), industry (24.6 percent) and agriculture (4.7 percent). Unemployment declined in all three sectors compared with the same month of 2016.