Thomas “Tommy” Gambino, the oldest son of crime family founder Carlo Gambino, has died.

He was 94.

The longtime Upper East Side resident died Oct. 3 of natural causes.

The New York Times reported in 1992 that the Mafia captain had “at least $75 million in cash, bonds and blue chip stock.”

He was the nephew of “Big Paul” Castellano, who succeeded Carlo as the head of the family but was rubbed out in 1985 on the orders of eventual Gambino godfather John Gotti.

Tommy Gambino arrived at Sparks Steakhouse on East 46th Street just moments after Castellano and his driver, Tommy Bilotti, were gunned down outside the eatery.

Tommy Gambino, once described as the a “quintessential Mafia prince of New York City,” was convicted in 1993 of two counts of racketeering and racketeering conspiracy for controlling gambling and loan sharking operations in Connecticut.

He served in federal prison from 1996 to 2000.

The prosecution’s evidence in his trial included secretly recorded conversations with Mafia turncoat Salvatore “Sammy the Bull” Gravano.

Thomas’ younger brother Joseph, who never became a made man, died in 2020 at the age of 83.

In 1992, the brothers — who owned a trucking monopoly Consolidated Carrier Corporation on West 35th Street with several companies in the Garment District — were charged with enterprise corruption and 52 counts of larceny, extortion, coercion and restraint of trade, which meant a possibility of 25 years in prison if convicted.

Then-assistant district attorney Eliot Spitzer led the investigation that ultimately brought them down, “figuring out a way to break into the duo’s office to plant a bug — by using Con Ed trucks on a phony repair call, by picking locks, switching off alarms, and evading motion detectors — then listening to hundreds of hours of tapes,” according to New York Magazine.

The brothers took a plea deal, agreeing to shell out $12 million in fines and restitution and sell their trucking businesses.

Then-assistant district attorney Eliot Spitzer led the investigation that ultimately brought them down, “figuring out a way to break into the duo’s office to plant a bug — by using Con Ed trucks on a phony repair call, by picking locks, switching off alarms, and evading motion detectors — then listening to hundreds of hours of tapes,” according to New York Magazine.

“I send my condolences to his family,” Spitzer told The Post.

Thomas married Mafia boss Tommy Lucchese’s daughter Frances, who is now 92. They had one son, Thomas Jr., 63.