Cuomo Earned Almost $5 Million Consulting. He Won’t Name His Clients.

Former Gov. Andrew M. Cuomo earned nearly $5 million working as a private consultant in 2024, a sum so large it puts him in the top 0.5 percent of New York City earners, according to his annual tax returns.

The tax documents, reviewed by The New York Times on Tuesday, show that Mr. Cuomo derived $4,712,978, almost all of his income last year, from Innovation Strategies, a pass-through company created for his consulting work before he ran for mayor of New York City.

By using his company as an in-between, Mr. Cuomo avoided having to disclose the individual clients who paid for his services. His campaign said he had stopped his private work earlier this year, but it has repeatedly refused to say who was paying him.

The arrangement, while well within the law, makes it almost impossible for voters or watchdog groups to understand the financial and business connections of someone who could soon have sway over billions of dollars in public contracts, real estate developments and city policy.

Mr. Cuomo, who is running as a third-party candidate after losing June’s Democratic primary, was the last major mayoral candidate to agree to share his tax documents. He did so only in the waning days of the campaign as early voting was underway.

The former governor, 67, was the highest earning candidate in the race last year — by a factor of more than 10.

Zohran Mamdani, the Democratic nominee and front-runner, reported $131,398 in income from his job as a state assemblyman. He took in another $1,267 in royalties related to an earlier music career, according to his tax documentation.

Returns shared by Curtis Sliwa, the Republican nominee, showed that he earned $423,000 last year from WABC, a conservative talk radio station where he hosted a show. Mr. Sliwa has since taken a leave of absence to run for mayor.

The candidates had provided some broad financial information about their 2024 income and assets in public disclosure forms filed with the city. But their tax records give a far more precise picture of their financial status in a race and a city consumed by questions of wealth and affordability.

For instance, on their city financial disclosure forms, the candidates only had to report income in broad ranges. Mr. Cuomo, for example, checked a box saying that he made $500,000 “or more” from Innovation Strategies in 2024.

His federal tax return, though, showed $4,910,599 in adjusted gross income. That included his consulting fees, as well as a roughly $50,000 state pension and about $230,000 in dividends, interest and other capital gains.

Rich Azzopardi, a spokesman for Mr. Cuomo, said his lucrative work should be “no surprise” given his experience at the highest levels of government. “What sets him apart is that he walked away from it to serve again,” he said.

Still, the large sums could complicate lines of attack by Mr. Cuomo, who has tried to portray himself as the working-class rival of Mr. Mamdani, the son of an award-winning filmmaker.

The tax documents, filed in mid-October after Mr. Cuomo received an extension, show that he declared himself a resident of New York City for all of 2024.

Altogether, he paid nearly half his income, around $2,430,000, in federal, state and city taxes. (He also reported donating $75,000 to unspecified charities.)

Mr. Mamdani paid a little more than $34,000 in federal, state and local taxes. Because he was not married until 2025, he filed an individual tax return.

Mr. Sliwa and his wife paid $125,000 in total taxes.

Mr. Cuomo’s returns reflected a sharp upswing in his financial fortune in recent years. Though he secured a $5.1 million advance for a book on his leadership during the Covid pandemic, he had been paid at comparatively modest government rates for nearly two decades as governor and New York’s attorney general.

Within a year after he resigned from office in August 2021 in a sexual harassment scandal, Mr. Cuomo had formed Innovation Strategies to provide private consulting services and inked a deal to make a podcast for more than $40,000 a month, The Times reported on Wednesday.

The show only lasted about a year. His consulting business evidently picked up steam, though it is difficult to know precisely what kind of work Mr. Cuomo was doing as long as his clients remain a secret.

One was OKX, an offshore cryptocurrency exchange that hired the former governor in 2024 as it came under scrutiny by the F.B.I. and federal prosecutors for operating illegally in the United States. Mr. Cuomo advised the company on how to respond to the inquiry, Bloomberg first reported.

The company agreed to plead guilty to violating U.S. money laundering laws in February, shortly before Mr. Cuomo entered the race. It has not disclosed what it was paying Mr. Cuomo.

The former governor also signed a consulting contract with another company, Nano Nuclear Energy, in 2024 and joined its advisory board, according to the company’s filings with the Securities Exchange Commission.

Mr. Cuomo’s exact responsibilities with Nano Nuclear were unclear. He once lent his name to a company news release. The full advisory board apparently met only once, at a hotel in Manhattan just days before Mr. Cuomo resigned from the body to run for mayor, and he spoke at the meeting only briefly, according to two of its members.

But the arrangement was potentially quite lucrative. The filings show that the company granted him stock options just months before it went public. They are now worth more than $5 million.

The Times has reported that Mr. Cuomo also pursued a luxury marina project in Puerto Rico with the real estate investor Andrew L. Farkas, but it fizzled and the former governor said he was never paid.

Mr. Azzopardi said Mr. Cuomo would not comment on “private client matters” but said that none had involved city or state agencies.

“If elected, Governor Cuomo wouldn’t have any position other than to serve as mayor of New York City, and would work with the Conflicts of Interest Board to navigate any perceived issues that may arise,” Mr. Azzopardi said.

Ethics experts said the secrecy was far from ideal.

“‘Trust me’ is never a good answer in a context of ethics and potential conflicts of interest,” said Richard Briffault, a former chairman of the New York City Conflicts of Interest Board. “The whole point of the thing is to make sure there is an outside review looking in.”