"Some of the people I speak with are on low hours and need more," First Union Hawke's Bay organiser Mike McNabb said.
"There's people who can't get enough hours at work, so they've got two and three jobs to make ends meet. This may be nightfill workers doing other jobs during the day, and day workers doing extra jobs at night."
Workers and families were suffering as a result, he said.
Nationally, the unemployment rate dropped to 6.9 per cent in the three months to December. That was down from a 13-year high of 7.3 per cent in the September quarter, according to the household labour force survey.
However, the number of working age people in employment has also fallen with 23,000 fewer Kiwis in jobs.
"We're seeing fewer people working and looking for work, and more people outside the labour force," Diane Ramsay of Statistics NZ said.
"More younger people are solely in study and more older people are entering retirement."
The employment rate fell 0.8 per cent for the December quarter to 62.6 per cent. A breakdown showed the fall was due to a 6 per cent decline in part-time employment. Fulltime employment rose by 0.4 per cent.
Westpac economists called the survey an "oddball assessment" of the labour market.
"Our assessment of the labour market has not really changed - it is still weak, but we do not believe that it has suddenly gotten sharply better or worse."
Year-on-year figures showed the total number of Kiwi jobs fell 1.4 per cent in the 12 months to December. This was led by a 19 per cent plunge in self-employment, which has been falling from a peak in December 2011.
Otago had the lowest unemployment rate across the regions at 4.3 per cent, with Southland at 4.6 per cent and Canterbury at 4.9 per cent. Auckland's unemployment rate improved to 7.2 per cent, while Wellington's rose to 7.9 per cent.
Northland had the highest unemployment rate at 9.5 per cent.
Labour's finance spokesman David Parker said workers in the manufacturing sector had struggled in the past year.
"[It] was a bad year for workers in the manufacturing sector. There were 17,200 fewer people in jobs at the end of it with the number falling every quarter."
Tertiary Education, Skills and Employment Minister Steven Joyce said the survey reflected the "ongoing impact of tough economic times globally".
New Zealand's unemployment rate is now the 14th lowest among developed nations, below Canada's 7.2 per cent and above Israel's 6.7 per cent.
