Nearly a quarter (22%) of workers say that money worries have harmed their performance at work, research for the Building Societies Association (BSA) indicates.
Around a fifth (19%) of people surveyed said they needed to take time off work due to illness caused by financial concerns.
The research indicated that young adults have been particularly affected.
A third (33%) of workers aged 18 to 24 said their money worries have made them ill and forced them to take time off work.
The BSA warned that many people in the UK are living without a savings buffer.
Over a quarter of UK adults (27%) have less than £1,000 in savings, while 12% have no savings at all, its research indicated.
A fifth (21%) could not cover a £300 unexpected expense and three in 10 (30%) would not be able to live off their savings for more than one month if they lost their income.
Nearly half (44%) among those aged 35 to 44, who are often parents of young children, said they would not be able to live off their savings for more than one month if they lost their income.
Four-fifths (81%) of people said they could save an extra £10 a month if they needed or wanted to, including nearly half (47%) of those who said they have no savings at all.
Shirley Ballas, Strictly Come Dancing head judge, who is supporting UK Savings Week said: “I’ve seen first-hand how life can throw unexpected challenges your way, and how important it is to build resilience to face them.
“This research shows just how deeply money worries can affect our wellbeing. But it’s also encouraging to see that many people who aren’t currently saving feel they could start building a regular savings habit.”
Andrew Gall, head of savings and economics at the BSA said: “This research lays bare the human cost of financial insecurity and how money worries are quite literally making people ill.
“But the findings also highlight the benefits of saving. We know that those who are able to save, even small amounts, have reduced anxiety and are more able to deal with life’s shocks. And for people fortunate to have more substantial savings pots, having savings to draw upon can open up new opportunities.
“UK Savings Week encourages everyone to build better savings habits, whatever their starting point. Whether it’s £1 or £100, every pound put into savings helps to build peace of mind, long-term resilience, and better mental wellbeing.”
The BSA research was carried out by Opinium, among 2,000 people across the UK in June.
Running from September 22 to 28 2025, UK Savings Week is a BSA-led campaign to engage people with saving.