Snap's chief strategy officer Imran Khan is to exit the business to "pursue other opportunities".
The company has not yet found a replacement and Khan, who has been at Snapchat since 2015, will continue to serve as chief strategy officer in the interim.
Snap will not rehire for the role of chief strategy officer, instead hunting for a 'chief business officer' to fill Khan's seat. He will aid the search.
According to Bloomberg Khan is poised to start his own investment firm that will take stake in technology companies.
Khan's departure was revealed via an SEC filing in which Snapchat said the "transition" was not related to any disagreement with the business on any matter relating to its "accounting, strategy, management, operations, policies, or practices (financial or otherwise)."
Snap boss Evan Spiegel said: "Imran has been a great partner building our business. We appreciate all of his hard work and wish him the best."
A former JP Morgan and Credit Suisse exec, Khan has helped scale up Snap's ad offering over a short period and contributed to its revenue growth which clocked in at $262m for the most recent quarter.
The chief strategy officer was also at the helm during the firm's buzzy IPO and the rebrand of its parent company from Snapchat to Snap Inc.
In an email to staff, he said: "After nearly four years at Snap, I have decided to step down. This has been a very difficult decision for me to make. There is never a perfect time to say goodbye, but I know that the time is now. We have a stellar leadership team in place to guide Snap through the next phase of growth and on to the next chapter."
He added: "I’m not going anywhere just yet. I will be focused on identifying a CBO and ensuring a smooth transition. We won’t miss a beat during this period, and you will be left in better hands than my own."
Earlier this year, Snap's former head of sales Jeff Lucas joined Oath as vice-president of American Sales.
In August, Snap hired Kristen O’Hara to be its global head of business solutions, filling a role similar to the top sales job that opened early this year. She was poised to report into Khan.