Internet payment provider WorldPay has been criticised for making small businesses wait months to receive their money, although it blames the risk of online fraud for the delay.
The online clearing service is holding back payments for up to 12 weeks, leaving analysts to advise businesses to shop around to get the best deals on terms.
Initsys, a company selling security cameras for companies and homes, signed up with WorldPay, owned by the Royal Bank of Scotland, for e-commerce payments.
Chris Berry, founder of Initsys, said: "We started the business about a year ago and wanted to allow internet shopping, and chose WorldPay as recommended by our bank. At the eleventh hour WorldPay told us that our settlement period would be changed from two to eight weeks."
Initsys is now using an online payment service provided by HSBC, which is offering a three-day settlement period.
Simon Fletcher, communications manager at WorldPay, said it was difficult to comment on individual cases, but that settlement periods are made on a case by case basis.
"Risk assessments govern how quickly we settle funds. Settlement periods vary. They can take two weeks, four weeks, eight or 12," he said.
"With cardholder-not-present transactions over the internet, there is no signature and we manage the chargeback risk. We take on a lot of small, new and inexperienced businesses and we must retain the money made from websites as there is an increased risk of chargeback.
"If we didn't operate this model we couldn't do it, or offer such keen prices. E-commerce is a growing medium and one where we can we offer a slice of the pie even to companies with no trading history."
But Aneet Shah, head of capital markets - business services at Bloor Research, said: "Online payment settlement has to be quick. Almost everything about e-commerce is in real time, so people expect results instantaneously.
"Online commerce is based on building up a large consumer base and getting the money quickly."
If this does not happen, "the business model will fail as companies need a revenue stream. Even two weeks is not appropriate for payment providers to sit on the interest," he added.
Shah advised companies to shop around for better deals. "I am not surprised that HSBC offers a short settlement period as their strong point is bringing a good service to SMEs."
A spokesman from the Federation of Small Businesses said: "The system for processing credit cards online should be dragged into this century. Taking eight weeks to process payment is unacceptable."
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