The recession has started to hit online sales growth as the exponential increases once experienced by the e-tail market have begun to slow, according to new figures.

In June, year-on-year growth of online sales was 12.3 per cent, only half the level enjoyed in June last year.

For the second half of the year, IMRG Capgemini, which publishes monthly and yearly online sales figures, has reduced its growth forecasts from 15 per cent to 12 per cent. The change is partly due to the slowing of fashion sales online as young shoppers face the prospect of having less disposable income in a toughening graduate jobs market.

Sales fell 1.3 per cent in June compared with May, meaning that sales have declined every month in the second quarter of this year. Sales were hampered by recent warm weather as shoppers chose to go outside instead of shop online.

There is also increasing evidence that the number of consumers just “window shopping” is growing, with average conversion rates on shopping sites falling to just 5 per cent, compared with between 6 and 8 per cent over the past two years.

IMRG Capgemini also found that consumers, who are estimated to have spent £1.2bn on clothing, footwear and accessories online in the first half of this year, are going online more often to research products and that there is less brand loyalty.

Capgemini head of consulting for retail Mike Petevinos said: “While online is clearly showing signs of being affected by the recession, it is still faring better than the high street as consumers look to online to help them make better informed decisions during tough times.”

Earlier this month fashion e-tailer Asos said that although it was still experiencing strong growth, with sales up 52 per cent for the 13 weeks to June 26, it was slowing. Asos chief executive Nick Robertson said unemployment’s effect on spending was a continued concern.