A top executive at former President Donald Trump's family business pleaded guilty on Thursday for tax evasion on a free apartment and other benefits, reaching an agreement with prosecutors that may make him a key witness against the corporation in a trial this fall.

Allen Weisselberg, a senior Trump Organization advisor and former company CFO, pleaded guilty to all 15 charges brought against him in the case.

Weisselberg admitted to receiving about $1.7 million in untaxed extras, which include: school tuition for his granddaughters, free rent for a Manhattan apartment, and lease payments for a fancy car — and expressly keeping some of the goodies of the books in a quiet, somewhat scratchy voice.

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Judge Juan Manuel Merchan agreed to sentence the businessman to five months in New York's Rikers jail complex, with a possible early release for good behavior. The judge also ordered Weisselberg to pay over $2 million in taxes, fines, and interest, as well as be on probation for five years. 

The plea agreement requires Weisselberg's honest testification as a prosecution witness while the Trump Organization is tried on similar charges in October. The corporation is accused of assisting Weisselberg and other executives in avoiding income taxes by failing to fully declare their total salary to the authorities. Trump has not been charged in the matter.

Weisselberg will be released on bond until the conclusion of the company's trial. He said nothing as he walked out of court, refusing to answer a journalist's question about if he had a message for Trump.

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If Weisselberg does not comply with the plea requirements, prosecutors said they will pursue a "significant state prison sentence," and Merchan warned that he may face the maximum penalty for the top crime, grand larceny, of 15 years in jail.

Weisselberg’s lawyer Nicholas Gravante Jr. said his client pleaded guilty “to put an end to this case and the years-long legal and personal nightmares it has caused for him and his family.”

Trump Organization; a criminal organization? 

Manhattan District Attorney Alvin Bragg said in a statement that Weisselberg’s plea “directly implicates the Trump Organization in a wide range of criminal activity and requires Weisselberg to provide invaluable testimony in the upcoming trial against the corporation.”

“We look forward to proving our case in court against the Trump Organization,” he added.

Weisselberg's testimony might harm the company's defense. If convicted, the company might face fines of twice the amount of unpaid taxes, as well as probation and the necessity to adjust its business operations.

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Weisselberg agreed to enter a guilty plea days after Merchan dismissed his attempt to dismiss the allegations. The judge dismissed the defense's allegation that the district attorney's office was punishing Weisselberg because he refused to provide damaging information about Trump.

The district attorney is also looking into whether Trump or his corporation misrepresented to banks or the government the value of their properties to acquire loans or lower their tax obligations.