People now have nine per cent of their take-home salary left each month, up from four per cent in the previous quarter, according to the Disposable Income Index from Scottish Friendly.
Researchers believe the rise may be accounted for by an increase in the number of Scots in work rather than struggling on benefits.
Earlier this month official figures showed that the number of Scots in employment increased 16,000 last quarter, with 2,578,000 people in some form of work.
Scotland and London now top the disposable income tables for the last quarter, with people in each region having typically £263 left over each month after essentials are paid for. In Scotland it represents a 65 per cent rise in disposable income from the previous quarter. Wales and the north-east of England lag behind, with £193 and £182, respectively.
The survey also found the increase in disposable income has prompted a rise in the levels of saving.
Now 67 per cent of people in Scotland put money aside each month, up eight percentage points since the last index. That compares to 60 per cent across the UK.
And Scots are starting to feel more confident about their financial situation, with just 15 per cent of people believing that their financial situation will worsen in the next three months, down from 19 per cent last quarter.
One in five Scots says that in the next three months their focus is on paying off their debts, while a further 11 per cent say their top priority is to avoid getting into debt.
Both are indicators of an improving savings and investment culture in the UK.
Neil Lovatt, product director at Scottish Friendly, said: "The results show a stronger mood of personal responsibility among savers in Scotland, across all income levels."