Internet-savvy Britons are spending more than ever before online, particularly on auction websites such as eBay, according to credit and debit card association Apacs.

Its figures reveal that more than half of adults made an online purchase last year and that a record £2.8 billion was spent on auction sites alone.

The average number of online purchases made by shoppers also rose from 13.6 in 2004 to 18.5 in 2005 and the value of internet card transactions increased £6 billion to £22 billion.

Apacs’ findings on internet shopping support those of Orange Broadband. It recently released figures showing that about one in two British adults are now profiting by selling goods online, with the average vendor making £341 in the past 12 months.

Internet crime is also on the up, however, as crooks frustrated by the introduction of chip-and-pin technology turn their attentions to internet and telephone fraud, for which they do not need your four-digit pin.

Apacs is warning people shopping and trading online to be aware of the threat of fraud – particularly when using online auction sites.

Sandra Quinn of Apacs said: "The internet is now very much part of mainstream culture in Britain. However, consumers must be alert to the threats posed by internet criminals, and take steps to protect themselves when shopping online. We all need to be careful with our cards and personal details."

Websites such as getsafeonline.org, cardwatch.org.uk and dolceta.eu offer advice on making the most of online shopping without falling victim to fraud.

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