Coupang’s debut is the biggest for a foreign company since

Alibaba Group Holding Ltd.

’s blockbuster 2014 debut. Coupang expects proceeds of $3.5 billion from the offering. Its stock trades under the symbol CPNG on the New York Stock Exchange.

Founded in 2010 and backed by Japan’s

SoftBank Group Corp.

, Coupang has become one of the three largest private-sector employers in South Korea. While Amazon.com Inc. and Alibaba have dominated e-commerce in most of the U.S. and international markets, Coupang has created a rare moat around South Korea, fending off both global giants in its home turf.

The public offering comes as the mania that gripped the red-hot IPO market last year hasn’t shown signs of abating. So far in 2021, 311 companies have done U.S.-listed initial public offerings, according to Dealogic. That compares with 36 at this point last year. Alternative methods of going public such as releasing existing shares for direct sale to investors and combining with a special-purpose acquisition company have also gained steam.

Coupang had more than 100 fulfillment and logistics centers in some 30 cities at the end of last year, with more than 40,000 workers handling orders, according to a securities filing. It has built its own delivery system and promises customers that items ordered before midnight can be delivered before dawn the following morning. The company also allows customers to return items by simply leaving them outside their doors and delivers many items in reusable containers that its workers pick up later.

Coupang posted a net loss attributable to unit holders of $567.6 million for 2020, narrower than the prior year. Its net revenue nearly doubled to $11.97 billion in 2020. It said roughly $128 billion was spent on e-commerce in South Korea in 2019, a figure expected to grow to $206 billion by 2024. The company also offers grocery delivery and other services.

Like most Silicon Valley founder-led companies, Coupang employs a dual-class structure as it sells stock to investors. Bom Suk Kim, Coupang’s chief executive and founder, has a class of stock with 29 votes per share compared with one for anyone buying into the IPO. Coupang has raised funding from investors including Greenoaks Capital, Sequoia Capital,

BlackRock Inc.

and hedge-fund investor

William Ackman.

Recent IPOs have occurred against the backdrop of feverish demand and led to soaring debuts. Shares of

Airbnb Inc.,

Snowflake Inc.

and

DoorDash Inc.

skyrocketed on their respective first days of trading in 2020 after underwriters priced them above initial expectations.

Roblox Corp.

shares rose 54% in their debut Wednesday.

—Maureen Farrell contributed to this article.

Write to Dave Sebastian at dave.sebastian@wsj.com