Ivanti’s research also revealed a growing psychological toll.
According to new research, nearly a third of UK employees using generative AI tools are keeping it secret from their bosses.
The study by US-based enterprise software firm Ivanti found that 29% of workers were using artificial intelligence in their jobs without telling their employers.
Some said they feared losing their jobs, while others admitted they liked having a “secret advantage”.
Despite ongoing concerns about cybersecurity, AI use is rising fast in UK workplaces.
In 2025, 49% of employees reported using AI at work. This is an increase from 32% the year before.
Of those, 28% said they feared being fired if their employer found out they were using AI tools.
Another 38% said they enjoyed the edge it gave them.
Ivanti’s research also revealed a growing psychological toll.
More than one in four workers (27%) said they felt “AI-fuelled impostor syndrome” and worried others would question their competence.
Meanwhile, 30% of employees who use GenAI tools at work worry their job may be cut.
Brooke Johnson, Ivanti’s chief legal counsel, said: “Employers who fail to approach innovation with empathy and provide employees with autonomy run the risk of losing valuable staff and negatively impacting employee productivity.”
She added that secret AI use could put firms at risk of cyberattacks, breach contracts, or expose sensitive data.
Johnson said: “Workers adopting the technology without proper guidelines or approval could be inviting cyberattacks, violating company contracts or risking valuable company information.”
Ivanti urged companies to introduce clear governance rules while giving staff access to AI tools that support productivity.
The findings pointed to deeper workplace dissatisfaction.
Forty-four per cent of employees said they were suffering from “resenteeism”, staying in a job they no longer enjoy.
Another 35% said they were engaging in “presenteeism”, showing up or logging in just to be seen, not to be productive.
Examples included logging in early without working or moving a mouse to appear active on platforms like Slack.
The study also highlighted a growing gap between staff and management expectations.
While employers hoped office returns would boost output, workers increasingly prioritised flexibility.
Half said they would consider quitting for more flexible working hours.
Sixty-one per cent said rigid schedules made them feel undervalued.