Following its expansion across 10 European countries last December, mobile point of sale provider SumUp announced today it has signed a deal with American Express that will allow its merchants to accept American Express cards.

"It's extremely frustrating for a merchant when they miss out on making a sale because they can't accept the type of card a customer wants to use," said SumUp CEO Daniel Klein. "The only person it's more frustrating for is the customer who goes away empty-handed. That's why we're delighted that we will be able to process American Express card payments on behalf of our merchants and to the advantage of American Express' thriving and deeply loyal customer base."

The European mPOS market is becoming as crowded as that in the U.S. SumUp is competing with other European mPOS providers like payleven, mPowa and iZettle to expand its footprint across the continent, and the ability to accept American Express will enhance its value proposition to small merchants.

Like other mPOS providers, SumUp helps small merchants accept credit and debit card payments through a mobile device and charges 2.75 percent per transaction. SumUp said the transaction fee for American Express will be the same as those charged for Visa and MasterCard. Additionally, the SumUp reader is EMV compliant, meaning it accepts cards with embedded EMV chips.

According to SumUp, Amex acceptance will be rolled out to eight of the 10 markets it currently services in Europe first, with Portugal and Belgium to follow soon.

Launched in the U.K. in 2011, SumUp currently offers services in the U.K., Germany, Ireland, Austria, the Netherlands, Spain, Italy, France, Portugal and Belgium.

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