The seasonally adjusted Live Register total decreased by 2,100 from 159,100 in December to 157,200 in January, according to the latest figures from the Central Statistics Office.
This compares with an increase of 300 in January of last year.
The unemployment rate last month was steady at 4.2%.
The CSO said that in the year to January 2005, there was an unadjusted decrease of 13,986 on the Live Register.
This compares to an unadjusted decrease of 11,788 recorded in the year to December 2004.