The BPIF spoke out after national fraud and cyber crime agency Action Fraud and fraud prevention service Cifas flagged up a sharp rise in the number of attempted so-called fake invoice scams.

More companies reported falling victim in the first half of this year than in the whole of last year, say the two groups.

Criminals posing as a supplier claim their company’s account details have changed. An employee then changes the supplier’s account and when the fake supplier files its invoices, the money is paid to the criminal's account.

Another scam involves submitting fake invoices made out to be from a real supplier. Between January and June 749 cases were reported against 603 for the whole of last year and 739 in 2013.

But the two fraud-prevention organisations believe the real figure is higher because many crimes go unreported, meanwhile criminals often strike in summer when experienced staff are on holidays.

BPIF head of legal Anne Copley said: “It’s so easy in a busy production environment to take these interventions at face value without properly checking.

“After all, something that looks like it comes from a known and trusted supplier is likely to be considered low risk. But all it takes is a quick telephone call.

“You should phone the supplier’s accounts department as a double-check and I suggest building that into your normal accounts procedures.”

Cifas chief executive Simon Dukes said fraudsters often took advantage of organisations with fewer resources and staff.

“This leaves small businesses more vulnerable to fraud. But greater awareness is a powerful tool in fraud prevention,” he said.

Head of Action Fraud, which is run by the City of London Police, Pauline Smith said: “It is important employees are made aware of invoice scams and are ready to recognise the signs of fraud.

“Incidents of invoice fraud are underreported and therefore it is difficult to know the true scale of this fraud type.

“However what we do know, is this type of fraud prevails across all types of business and no one type of industry is immune.”

Tips for businesses to protect against invoice scams:

• Ensure all staff, not just finance teams, know about this fraud - especially those covering roles during the holidays
• Never respond to the contact details provided by someone requesting changes to financial details. Instead, use established email and telephone contacts to check that any request has come from the genuine supplier
• Always review invoices to check for inconsistencies/errors, such as a misspelt company name
• Where possible establish at least two specific points of contact with suppliers so that all invoice changes can be confirmed with both contacts
• Contact suppliers for payment of larger invoices in advance of making payment to ensure that payment is made to the correct bank account
• Consider what information is publicly available about your business and whether it needs to be public
• Never leave invoices unattended in the office or on a desk
• Ensure your computer systems are secure and that antivirus software is up to date

Fraud and cyber crime can be reported online at www.actionfraud.police.uk or by speaking to a fraud and cyber crime adviser on 0300 123 2040. Visit: www.cifas.org.uk