A spokesman said the Dutch company, which handles customer payments for the likes of Uber, Facebook and Netflix, had gained new customers after the June collapse of German rival Wirecard, but the impact on revenue and earnings was negligible.

Core earnings (EBITDA) for the six months to June 30 reached 141 million euros ($167 million), up 11.9% from a year earlier - down from growth of 16% in the first quarter before the pandemic slowdown began to bite.

Revenue rose by 27% to 280 million euros, versus first-quarter growth of 34%.

Shares, which have doubled in value this year and have risen more than 500% since the company's 2018 market debut, fell by 5% to 1,387 euros by 0841 GMT.

"Although the results still show strong coronavirus resilience ... (they) might not confirm the exceptional share rally of these past three months," said analysts at KBC in a note.

Adyen also processes payments for airlines including KLM and clothing retailers such as Zalando, which have been among the sectors most affected by the COVID-19 pandemic.

Since April travel volumes have begun a slow recovery, CEO Pieter van der Does said in a letter to shareholders.

"Simultaneously, the upward trend in online retail volume persisted even though lockdown restrictions eased in some geographies," van der Does added.

The spokesman said Adyen had picked up some customers left without a payments processer after Wirecard's insolvency, mostly in Asia.

About 80 percent of sales growth came from existing customers during the first half, the company said.

By Toby Sterling