More than 50 union members, and a giant inflatable rat, protested outside the ANZ's headquarters in Wellington this morning.
ANZ workers from First Union are protesting against rotating shifts and a pay rise of 2-3 per cent, compared to the 14% they claim management got.
Union member Bella Pardoe says the new scheduling system means workers only find out three weeks in advance what their schedule will be.
The union wants just 20 per cent of workers on flexible schedules, and a pay increase similar to the 3.4 per cent Westpac workers received recently.
A spokesman for ANZ said it was a "very good offer" on the table.
"ANZ has offered staff pay increases of 3% and 2.75% over the next two years, much higher than the latest increase in cost of living (1.6%) and the average increase in wages (1.7%).
All ANZ branches will remain open during the protest action, he said.