The National Distribution Union says its members have been receiving wage increases of up to 6% per year both during the recession and since.
The Public Service Association says its members will be pushing harder for wage increases now the economy has had 12 months of growth.
It says members have had to share the pain, now they should share the gain.
The National Distribution Union says general wage increases averaged 0.3% nationally in the first three months of the year.
Union president Robert Reid says there is never a good time to ask for wage increases, but NDU members have been achieving rises of between 3% - 6% per year.
The Northern Employers & Manufacturers Association says wage increases depend on the circumstances of individual companies.
Chief executive Alasdair Thompson also says people need to remember that wage rates generally did not go down during the recession and some even went up.