More than one in five Britons are so financially stretched they are struggling to make ends meet, according to financial website moneysupermarket.com.
Around 22% of people said the cost of living was now so high that they would be unable to cope if their bills rose any more.
A further 30% said an increase of less than £100 a month to their living costs would be enough to tip them over the edge.
Households have seen their outgoings rise by an average of £54 a week in the past six months, leaving them with just £247 a month to spare after they have met all of their essential outgoings.
Four out of 10 people blamed their financial situation on the cost of petrol, saying hikes in fuel prices have had the biggest impact on their spending.
The situation may get worse if interest rates rise, with 22% of people worried about higher mortgage repayments.