According to Badenoch & Clark, 31% of employees are job-hunting with 5% looking to leave their profession entirely. In contrast, only one in ten said they felt refreshed post holiday and were ready to pursue a promotion.
Londoners had the worst post holiday blues with almost half (43%) being committed to finding a new job or leaving their profession entirely.
Those working in the financial sector felt the most negative (64.3%), arguably due to the doom and gloom of the current economic climate, with lawyers a close second, at 59%.
Heidi Waddington, associate director of Badenoch & Clark, said: "Whilst a holiday provides rest and relaxation, workers also have time to reflect and often come back to work feeling like the grass may be greener elsewhere.
"With schools going back and summer ending, September traditionally sees a shift in momentum within the labour market, and this year is no different.
"Over the past two years workers have been put under pressure, as many businesses have cut costs, with some making redundancies and others failing to replace personnel that have left. This has resulted in greater workloads and poor morale within the workplace."