As part of the extension, the online payment company will look into developing the's digital wallet.
PayPal boss Dan Schulman mentioned that deal in a LinkedIn post early Friday.
"This is another significant milestone on our journey to be a platform partner of choice, helping to enable global commerce by connecting the world's leading marketplaces and payment networks," he wrote.
Uber didn't immediately respond to request for comment on the PayPal announcement.
Earlier this month, the company's self-driving tech group got a $1 billion investment led by Toyota and it publicly filed with the US Securities and Exchange Commission for a potential $120 billion initial public offering. On Friday, it of $44 to $50 a share.