This group, mainly millionaires, own around five times as much as the poorest half of the population, who between them have just 9 per cent.
Meanwhile the most common type of household - couples with children - saw their average wealth fall by 3 per cent 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 figure 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 per cent of households had assets of £1 million or more.
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 narrowing the 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."