This is a rise of 12.9% or £1.2 trillion since 2006/08 when it was £9.1 trillion.
The overall increase in wealth was mainly down to an increase in pension wealth. Between 2006/08 and 2008/10, overall pension wealth increased from £3.6 trillion to £4.8 trillion. But pension wealth was not distributed evenly.
For households with pension wealth, the top 10% had pension wealth totalling £2.4 trillion, with the bottom 10% having only £0.008 trillion (£8 billion).
The report also shows that across Great Britain, 64% of people were not paying in to a private pension in 2008/10, with 42% of adults having no private pension savings at all.
Only 36% of individuals personally contributed to a private pension in 2008/10. And much higher proportion of employees in the public sector (82%) belonged to a current occupational pension scheme than their counterparts in the private sector (38%).
The median value of current occupational pension wealth of employees in the public sector (£90,100) was more than double than that of employees in the private sector (£40,000).
In 2008/10, median wealth held in private pensions from which individuals had not yet drawn an income (i.e. current and retained pensions) was much higher in defined benefit (DB) pensions (£93,900) than in defined contribution (DC) pensions (£16,000). Some people accumulate wealth in both DB and DC pensions.
In 2008/10, 18% of individuals received income from a private pension. The median wealth held in pensions that were already being paid (pensions in payment) was £79,400. A higher proportion of men (20%) than women (16%) received such income. The median level of wealth held by men (£126,500) in pensions in payment was more than double than that of women (£60,500).
Aggregate household private pension wealth in Great Britain increased from £3.7 trillion in 2006/08 to £4.8 trillion in 2008/10. However, around half of this difference (48%) was due to the change in financial assumptions used to calculate current and retained DB pensions and pensions in payment.
Private pension wealth was unequally distributed with 26% of households in 2008/10 not having any private pension wealth. Of those who had some private pension wealth, the 10% of households with the highest levels of pension wealth had almost seven times as much pension wealth as households in the bottom 50% combined.
Jamie Jenkins, head of workplace strategy at Standard Life, said: "The recent ONS Wealth figures highlight a number of changes that have occurred in the level of pension savings.
"The raising of savings limits through Pensions Simplification in 2006 appears to have led to greater contributions from higher earners, as you would expect. This is likely to have skewed the figures for pensions wealth slightly, but the more restricted annual allowance of £50,000 introduced in 2011 will start to restore the balance.
"The imbalance between public and private sector wealth - although startling on the face of it - is actually quite understandable. Many smaller private sector employers either don't have a pension scheme in place or don't promote it, whereas pensions saving in the public sector is a more intrinsic and valued part of the benefits package. In essence, this illustrates exactly why we need to 'nudge' people in the private sector into pension saving, and auto-enrolment is key to that. The largest of the UK's employers are now able to auto-enrol all their employees into a workplace pension, and from October an obligation to do so will start to be rolled out to employers of all sizes.
"Auto-enrolment will likely mean over a million employers set up a pension scheme for the first time, and many millions more people join their workplace schemes, which has to be a good thing. So it will be interesting to review the balance between public and private sector pensions again in a few years' time. And also the level of savings in workplace pensions."
The ONS also revealed that total net financial wealth for all private households in Great Britain increased by £54 billion (5.3 per cent) to £1,085 billion between 2006/08 and 2008/10. Increases were seen in both household financial assets and liabilities, but the increase in savings outweighed the increase in liabilities.
