The richest 10% of British households own 44% of total household wealth, according to official figures that show this share has increased under the Coalition while families have become worse off.
This group, mainly millionaires, own around five times as much as the poorest half of the population, who between them have just 9%.
Meanwhile the most common type of household - couples with children - saw their average wealth fall by 3% between 2008/10 and 2010/12.
The data from the Office for National Statistics (ONS) showed the top tenth of society controlled £4.2 trillion of the total £9.5 trillion of assets - a slightly higher proportion than two years before.
Campaigners said it was "further evidence of increasing inequality" though the Treasury pointed to an inequality index figure published as part of the figures which had remained unchanged.
The figures showed the wealthiest fifth of households had 105 times more than the least wealthy fifth. They had 92 times more in the previous period.
Some 9% of households had assets of £1 million or more.
The data also revealed how London had prospered in spite of the downturn, with average wealth up 31% between 2006/8 and 2010/12, compared with an average across England of 11%.
In parts of the Midlands this was flat while families in the North East were 10% worse off over the period, as property wealth fell.
Half of all households had total wealth of £218,400 or more, up from £204,300 two years before. This "median" average measure was the highest in the South East, at £309,700, the figures showed.
The figures showed overall wealth had risen over the two years from £9 trillion, with the largest component coming from private pension wealth, standing at £3.6 trillion.
Property wealth stood at £3.5 trillion, with physical wealth - including the contents of homes, valuable and collectibles - at £1.1 trillion. This included personalised number plates, which the figures showed were owned by 7% of households.
Financial wealth - including current accounts, savings, bonds and shares as well as non-mortgage debts - was £1.3 trillion.
London saw the largest rise in this type of wealth between 2006/08 and 2010/12, up by 26%. But a quarter of all households in the latest period found themselves in "negative net financial wealth".
The figures also showed 25% of households in Great Britain had outstanding balances on a credit card, while 11% owned a property other than their main home and 24% had no private pension assets.
Rachael Orr, Oxfam Head of UK Poverty Programme said: "This is another shocking chapter in a tale of two Britains, further evidence of increasing inequality.
"We need our politicians to grasp the nettle and make the narrowing gap between the richest and poorest a top priority.
"It cannot be right that in Britain today a small elite are getting richer and richer while millions are struggling to make ends meet."
A Treasury spokesman said: "The main measure of wealth inequality has remained constant since this survey began in 2006."