The Live Register rose to a three-year high in September - a month when the seasonally adjusted number of claimants traditionally falls.
The number of people claiming unemployment benefits rose by 1.4 per cent last month. The seasonally adjusted Live Register rose to 164,200 last month, with 2,200 more people claiming Jobseekers Benefit or Allowance compared to August.
It is the first time in six years that the seasonally adjusted Live Register figure has risen in September. The re-opening of schools after the summer holidays generally see a drop in Live Register numbers as parents return to jobs and part-time teachers return to employment.
Bloxham Stockbrokers economist Alan McQuaid said there was anecdotal evidence that the numbers might have been impacted by building contractors letting staff go at the end of the traditional August holiday period for construction workers.
Opposition parties attacked the Government's record on jobs, with Fine Gael employment spokesman Leo Varadkar accusing it of complacency after "five years of easy credit, soaring property prices and a booming construction sector".
Labour Party employment spokesman Willie Penrose said there had been an "abject failure" to protect jobs at firms such as Lapple in Carlow and Tyco in Shannon, and a failure to close deals with major employers.
Despite the increase in claimants, the standardised rate of unemployment remained at 4.7 per cent, according to the Central Statistics Office (CSO).
Davy Stockbrokers economist Rossa White said the rise in claimants "was not a drastic increase by any means".
Although the total of people on the Live Register is at a three-year high, the labour force has increased so dramatically over that period that the increase was "hardly worrying", he said.
The static unemployment rate was encouraging in light of the number of building site closures, Mr White added, noting that firms might be "hoarding" building sector workers in the expectation that there will be a pick-up in demand for building services.
Other possible explanations for the slow increase in the number of unemployment claimants, given the decline in housebuilding activity, include a quick response from the labour force - a slower pace of immigration - or strong levels of job creation outside of the housing sector.
