Andersen has served as the company's vice president of finance since July. He previously spent seven years at Amazon, where he was also vice president of finance after a stint as finance director, and before that worked at Fox Interactive Media.
"Derek has played a critical role in building our finance function since joining Snap almost a year ago, as well as leading our cost efficiency initiatives and strategic planning processes," Snap CEO Evan Spiegel said in a statement.
Andersen's promotion comes a few months after the departure of Tim Stone, who served as Snap CFO for less than a year. The stock plunged 14% after the announcement of Stone's exit in January.
Lara Sweet took over as interim CFO at the time. Sweet, who has been with the company since June 2016, was named chief people officer on Monday.
Disclosure: CNBC parent NBCUniversal is an investor in Snap.