The New York store, the first in the city and the 12th location nationwide, is on the second floor in Brookfield Place, a high-end shopping mall and office complex that houses a Gucci store and office workers from banks and credit card companies.
Amazon told the Associated Press that it expects many of its customers to be workers looking to pick up a lunchtime salad or sandwich, people who live in the area or tourists visiting the nearby World Trade Center.
And if, for some reason, they forget their plastic or their mobile phones, they can pay for their purchases with cash.
The cash option differs from other Amazon Go stores that have opened in San Francisco, Seattle, and other mostly West coast locations. At its other shops, customers can only enter with an app that links to a credit card or an Amazon account.
The company, facing backlash from critics who say cashless stores discriminate against the poor, confirmed last month that it was working on a way to accept paper bill and coins. It was not clear whether its other stores will also be modified to accept cash.
Shares of Amazon opened down 0.46%, or $8.99, at $1,941.56 in early trading on the Nasdaq Stock Exchange. They ended the day Monday down 0.61%, or $11.91, at $1,950.55.