Instacart, the grocery delivery startup, disclosed in a regulatory filing Tuesday that it had closed a monster $210 million investment that a source says will increase to $220 million when all is said and done.

The investment is said to value the company at around $2 billion, a source previously told Re/code. The filing comes three weeks after Re/code reported the company was closing in on a big new investment led by Kleiner Perkins.

Just six months ago, Instacart was valued at about $400 million in a $44 million investment round led by venture capital firm Andreessen Horowitz. But the San Francisco-based startup has grown rapidly this year — 2014 revenue will be north of $100 million, or 10 times more than it was in 2013, CEO Apoorva Mehta recently told the New York Times. The company lets customers order groceries online from local stores such as Whole Foods and Costco and have them delivered on the same day. Instacart plans to expand into categories other than groceries in 2015, Mehta has said.

The massive investment comes as urban residents are showing a renewed interest in same-day delivery of groceries, more than a decade after delivery companies like Webvan and Kozmo burst onto the scene and then collapsed. Instacart is also capitalizing on concerns among big grocery chains about Amazon expanding its grocery delivery business, and they are taking advantage of surging investor interest in the category. The size of the raise signals that Instacart is intent on building a standalone business rather than selling to a big company such as Amazon or Google. Either way, the $2 billion valuation means an acquisition offer would have to be higher than most potential suitors are willing to spend.