Analysis of anonymised data from millions of bank accounts revealed the average notable upward change in pay in 2016-17 was 22 per cent, with the average decrease 20 per cent - more than a typical £250 monthly grocery bill.
Living standards think tank the Resolution Foundation called on firms and the Government to do more to mitigate the effect of irregular pay and support families’ ability to cope by reducing zero-hours contracts use and reforming Universal Credit.
The research, part-funded by the Nuffield Foundation, examined data from seven million Lloyds Banking Group accounts and found that pay volatility is the norm rather than the exception.
While pay increases - as a result of a pay rise, promotion or overtime - provide a boost, a sudden drop in income can be hard to cope with.
The report finds that more than four in five low-paid workers - those earning around £10,000 - experience pay volatility, compared with just two in three higher paid workers earning around £35,000.
And while a quarter of higher paid workers only ever experience upward changes in their monthly pay, pay volatility is more likely to go both up and down for low earners.
Daniel Tomlinson, research and policy analyst at the Resolution Foundation, said: “Much of Britain, from our bills to our welfare state, is built around a steady monthly pay cheque.
“But our research shows this is not the reality of working life for many of us.
“Around three in four workers experience big upward and downward changes in their monthly take-home pay.
“This volatility is a particular challenge for low-paid workers, who are less likely to have savings to fall back on when their pay packets shrink, and yet are more likely to have big falls in monthly pay.”