Fraudsters are increasingly targeting the public by stealing their card details to pay for illegal mobile top-ups. Such crimes are normally a pre-cursor to much larger raids on victims' accounts.

The transaction value is usually up to £30, which is small enough to go unnoticed on many people's statements.

If you spot a fraudulent payment, contact your card company or bank immediately as it will cancel your card or change your bank details to prevent any further problems (see the ID Protection guide). has witnessed a large rise in victims' complaints over recent months regarding bogus pay-as-you-go top-ups.

Many have complained in their droves on this site's forum of having transactions added to their bank or credit card statement when it is nothing to do with them.

Fraudulent payments to all the major mobile providers have been reported, though most complaints concern O2 top-ups.

The forum page where this fraud has mostly been reported has already been viewed over 36,000 times and includes hundreds of complaints (see the Mobile Top-up Fraud page).

Sandra Quinn, from fraud prevention organisation, the Financial Fraud Action group, says: "Fraudsters often try things out with smaller amounts such as this and, if it works, they will then try for much larger sums.

"They know many people will not notice these amounts on their statements. Always contact your bank or card provider if you've fallen victim."

Could networks do more?

Many victims have blamed mobile operators for not taking their concerns seriously and not doing enough to investigate the problem. There is absolutely no suggestion O2 or any other network is in any way involved.

One forum poster, Malc, said last week: "I've been had by this £30 O2 prepay UK scam today. I gave the O2 number a ring and asked to speak to the fraud department after explaining the situation but they seemed disinterested."

O2 says while it is sympathetic to fraud victims it cannot do anything about people's bank or credit card details being stolen in the first place.

A spokeswoman says: "We take fraud prevention and security very seriously and adhere to the security measures and authentication measures operated by banks.

"O2 only accepts payment where the security information and user's name and address have been verified.

"Anyone who thinks they have been wrongly charged by O2 should contact us.

"Our fraud department will take steps to help identify the reasons for the top-up and, if fraudulent, they will ensure the fraudulent handset cannot be used. We would also advise them to contact their bank."

Help prevent fraud

Archna Luthra, consumer products analyst, says: "This shows more than ever consumers need to be vigilant and regularly check statements. A simple monthly scan will quickly throw up any anomalies that can be rectified.

"Also, be wary of unfamiliar sites when shopping online and always check the security. This can prevent fraudsters lifting your details in the first place."

There are some simple steps to reduce your chances of becoming a victim of card fraud:

  • Look after your cards at all times and don't leave them unattended. Don't allow anyone to see your card or pin when making a transaction.
  • Safely store your statements, receipts and documents that contain sensitive information and shred them before recycling or throwing away.
  • Sign any new cards as soon as they arrive.
  • Cut expired cards through the chip first and then the magnetic strip.
  • Pay attention to card expiry dates. If your replacement card hasn't arrived call your bank or building society to check its status.
  • Ensure you are the only person who knows your pin and destroy any paper notification once received.

Further reading/Key links

Avoid email scams: What is Phishing?
Get ID protected guide: Do it for free
Protect your online accounts guide: Free Anti-Virus Software