Update: Added information from CICC.
The company said it has sold 53,292,401 ADSs through the at-the-market offering, raising gross proceeds of approximately $2 billion.
After deducting about $26 million in fees paid to distribution agents, the company received $1.974 billion.
NIO will use these proceeds to further strengthen its balance sheet, as well as for general corporate purposes.
NIO's sales agent for the share offering was CICC, a top Chinese investment bank, which said it was the largest ever at-the-market offering by an Asian company and the first at-the-market offering in the history of the Chinese auto industry.
Notably, NIO's original plan to list in Hong Kong was blocked, but the move will go some way to make up for the shortfall.
Earlier this year, its local counterparts XPeng Motors and Li Auto both completed Hong Kong listings, raising about HK$14 billion ($1.8 billion) and HK$11.8 billion ($1.5 billion), respectively.
NIO's latest fundraising is higher than the amount raised by XPeng and Li Auto through their Hong Kong listings.
NIO's move is expected to provide ammunition for the next new models and the expansion of its sub-brands.
NIO aims to deliver three products based on NIO Technology Platform 2.0 in 2022, including its flagship sedan ET7, which was launched earlier this year, the company said previously.
NIO will enter the mass market with a new brand, preparations for which have been accelerated and a core team has been established, William Li, the company's founder, chairman and CEO, said on the second-quarter earnings call.
"The NIO brand has a similar relationship to this new brand as Lexus has to Toyota, and Audi has to Volkswagen," he said.
Li said the VW brand NIO will launch hopes to be lower in price than Tesla, but the experience will surpass the latter.
NIO originally announced the offering on September 8 and said when it reported its third-quarter results on November 10 that it had sold 33,175,896 ADSs and raised about $1.2 billion.
After the company announced the plan, its stock fell nearly 17 percent from September 7 to October 6. After that, the stock rebounded. Although the stock has pulled back over the past week, it is up 14 percent since October 6.
It rose more than 2 percent in after-hours trading after NIO announced the completion of its at-the-market offering.