The news may come as a surprise to U.K. citizens who are still feeling the pinch, as economic growth remains subdued following the global financial crisis of 2007/08 and subsequent recession.
Official statistics suggest the economy was 0.6 percent smaller in the first quarter of 2014 than at its peak six years before.
However, Ashish Misra, head of investment policy at Lloyds Bank Private Banking, noted an upsurge in household wealth over the past year, with growth of £717 billion. This was the largest annual rise in a decade.
"Increasing activity in the housing market and continued growth in equity prices has boosted household wealth. These figures, to an extent, provide further evidence that the recovery in the U.K. economy is gathering pace," she wrote in Saturday's report.
Lloyds's measure of wealth covered financial assets, including bank deposits, government bonds, shares and pensions, as well as housing wealth. This latter has risen by £1.22 trillion or 58 percent since 2003.
"A booming housing market coupled with rising equity prices have resulted in a rapid expansion in the number of millionaires," Misra wrote.
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