The Democrat’s group plans two separate swearing-in ceremonies Thursday — a small, private one with his family in an old subway station around midnight, followed by a large afternoon event that will include a public block party outside City Hall.

As a new mayor The term will start immediately in the new year, it is customary for the future leaders of the city to hold two events. Outgoing mayor Eric Adams administered his first oath in Times Square shortly after the famous ball drop, while Adams’ predecessor, Bill de Blasio, took his first oath at home in Brooklyn.

On his part, Attractive swear by Manhattan’s former City Hall subway station — one of the city’s original stops on its subterranean transit system, known for its tiled arches and vaulted ceilings.

New York Attorney General Letitia James, a political ally and noted foe of President Donald Trump, will administer the oath of office.

The old City Hall stop was designed as the main station of the city’s first subway line, but was decommissioned in 1945. These days, aside from occasional guided history tours, locals usually only see it by staying on the 6 train after its last stop downtown when it turns north.

In a statement, Mamdani’s office said the choice to swear in the station shows his “commitment to the workers who keep our city running every day.”

“When Old City Hall Station first opened in 1904 — one of New York’s 28 original subway stations — it was a physical monument to a city that dared to be beautiful and build great things that changed the lives of working people,” Mamdani said.

“That ambition should not be a memory confined only to our past, nor should it be isolated only in the tunnels under City Hall: it is the intention of the administration fortunate enough to serve New Yorkers from the building above,” he said.

On Thursday afternoon, Mamdani will be sworn in again, this time by US Sen. Bernie Sanders, one of his political heroeson the steps of City Hall in a ceremony scheduled to begin at 1 pm US Rep. Alexandria Ocasio-Cortez, another political ally, will deliver opening remarks.

Mamdani’s transition formed an inaugural committee that included actor John Turturro, playwright Cole Escola and writer Colson Whitehead, as well as advocates, small business owners and campaign workers who the incoming mayor’s office said “provided vision, guidance, and cultural sensibility” for the ceremony.

The public swearing-in will be accompanied by a block party along Broadway to City Hall. Mamdani’s office expects thousands of people to attend and says there will be performances, music and interfaith elements.