As many UK workers believe they are likely to win the lottery (8%) as they are to be off work sick for 12 weeks or more (9%).
A survey for Cirencester Friendly revealed that 41% of workers thought they would last less than three months before they ran into financial difficulties if unable to work.
And the majority (53%) would depend on the state in the event of being unable to work due to illness or injury.
Average UK earnings are £488 per week, while statutory sick pay, payable for 28 weeks, is £88.45, although employers can pay more.
Figures from the Office of National Statistics showed that 2.5m people have been unable to work for three weeks or more and are claiming illness-related benefits.
However, the odds of winning the National Lottery jackpot are approximately one in 14 million, while the chances of matching five numbers and the bonus ball are around one in 2.3 million.
The survey of 1,332 people in full or part time work and 2,007 adults overall was conducted by YouGov for Cirencester Friendly.
Cirencester Friendly head of marketing Rebecca Young said these findings should serve as a warning to the whole UK population.
"Protecting earnings is an important aspect of sound financial planning; those who are unable to work due to illness or injury face a dramatic reduction in their income which in turn, results in difficulty making mortgage repayments or paying rent, buying food and paying bills."