(Adds interview) BERLIN, May 20 (Reuters) - Trade Republic, a leading European online brokerage that offers commission-free trading similar to Robinhood in the United States, said on Thursday it had raised $900 million from investors at a valuation of more than $5 billion. The funding round at Trade Republic, which was founded six years ago in Berlin and counts over a million customers in Germany, France and Austria, was led by Sequoia, the storied Silicon Valley investor that recently opened a London office. Co-founder Christian Hecker told Reuters that Trade Republic would invest the proceeds in expanding across the entire euro zone over the next two years, with market launches in Spain and Italy planned next. “We want to build the bank of the future,” Hecker said in an interview. “We are the only online broker in Europe that has a banking licence and its own technology.” Like Robinhood, which has spawned a new class of U.S. retail investor that has powered the latest bull market in stocks, Trade Republic offers commission-free investment via an easy-to-use smartphone app. The hype around retail investing has drawn attention to Trade Republic, Hecker said, adding however that its focus was on helping millennials invest over the longer term at a time of negative interest rates and pension shortfalls. Trade Republic offers free exchange-traded fund savings plans and commission-free investing in shares and cryptocurrencies. It manages 6 billion euros ($7.3 billion) in assets. Half of its customers have never invested before in their lives before signing up, said fellow co-founder Thomas Pischke. Sequoia backed Silicon Valley giants Apple and Google and more recently invested in Stripe, the payments company founded by two Irish brothers, and Klarna, the Swedish ‘buy now, pay later’ fintech that is eyeing a stock market listing. “The democratization of financial markets will be one of the most important consumer trends of the next decade,” Doug Leone, partner at Sequoia, said in a statement. “Trade Republic is on the leading edge of this trend and has attracted an untapped generation of European savers who demand increased financial accessibility.” Joining the investment round were TCV and Thrive Capital, as well as existing investors Accel, Founders Fund, Creandum and Project A. ($1 = 0.8209 euros) (Writing by Douglas Busvine, editing by Kirsten Donovan) Our Standards: The Thomson Reuters Trust Principles.