Nearly 17,000 people left the London Borough of Hillingdon to live elsewhere last year, more than half of them in their 20s and 30s, official figures show.

A total of 16,827 people left the borough in the year to June 2013. However, almost as many – 16,530 – moved in during the same period.

The resulting net migration figure of 297 was the tenth lowest of all 33 London boroughs, with Bromley experiencing the highest net influx at 2,046 people and Newham the greatest net migration at 8,007.

Of those who left Hillingdon, more than half – 9,070 – were aged between 20 and 39.

The Office for National Statistics (ONS), which compiled the data, found that tens of thousands of people in their 30s were leaving London altogether.

The ONS said a key reason for this was likely to be the cost of housing, with young couples looking to get on the property ladder but finding prices in the capital 'prohibitively expensive'.

Another factor, the ONS said, was that parents were looking for quieter, greener places to live.

Its report said: “Young couples wishing to buy their first house, or a larger one for a growing family, may find prices in London prohibitively expensive and therefore choose to live outside of London. The House Price Index (ONS, 2014) shows that in 2013 London had the highest average price for all dwellings in the UK at £428,000, well ahead of the South East at £305,000 and the East of England at £258,000. This was a 4.2 per cent increase from 2012, the highest across all regions.

“Another important reason may be that people with children are more likely to move out of London because of environmental or social factors. For example, they may be seeking somewhere greener and quieter, and may also perceive that a less urban neighbourhood offers a better social and educational environment for children. Moves of adults with children also explains why there is a net outflow of children from London.”

In 2012, a total of 17,120 people left Hillingdon, but 17,190 moved into the borough.

In 2011, 16,000 moved out and 15,800 moved in.

In the year to June 2013, 58,220 people in their 30s left London.