It was the first earnings report for the Amsterdam-based Adyen as a public company, whose wild initial public offering in June saw shares rise 100 percent from the IPO price of 240 euros per share.
Net profit in the first half rose to 48.2 million euros ($55.1 million), up 75 percent from a year ago. Sales soared 67 percent to 156.4 million euros.
"Our growth was mainly driven by existing merchants and we successfully added household names such as eBay, Valve and Dunkin' Donuts to our platform, CEO Pieter van der Does said in a statement.
The total volume of transactions processed by the company grew by 43 percent to 70 billion euros, Adyen said.
Adyen helps retailers take customer payments -- in any form and either online or in-store -- and usher them through complicated payment networks quickly. It operates globally, but more than half of transaction it processes derive from Europe.