The Big Apple’s best rat, Jona Rechnitz, thinks he should be sentenced to time served for his turn as a government witness — claiming his cooperation turned him into a persona non grata while constant threats and intimidation forced him to decamp New York for Los Angeles.

“Jona has also experienced more than sufficient punishment over the past several years of cooperation with the Government,” his lawyers wrote to Manhattan federal Judge Alvin Hellerstein, who will decide Rechnitz’s fate on Nov. 1.

“The shunning by his community literally drove him out of town, as he relocated this family to his hometown of Los Angeles.”

“Formerly unknown to the public, he is now known in New York as a ‘rat’ and a ‘snitch,’ whose every embarrassing episode has been reported in the tabloid press,” writes the defense, adding their client now lives “in fear of being accosted on the street by friends of the men he cooperated against.”

The former Manhattan real estate developer took the stand during three recent corruption trials where he admitted he’d schemed to lavish donations on Mayor Bill de Blasio in exchange for access to City Hall, and also bribed high-ranking NYPD cops with favors that included an all-expenses-paid trip to Las Vegas on a private plane, complete with a hooker dressed as a flight attendant.

His testimony led to the convictions of former correction union chief Norman Seabrook, Brooklyn businessman Jeremy Reichberg — once a close pal — and the guilty plea of hedge funder Murray Huberfeld.

Former NYPD Deputy Inspector James Grant, who allegedly shared a Vegas hotel room with then-hooker Gabi Grecko, was acquitted by jurors who said they didn’t believe her claims.

In addition to testifying at trial, Rechnitz sat down with prosecutors over 80 times, leading to the prosecution of some 15 people, the defense added.

Even after the move to LA in June 2017, Rechnitz says he was subjected to “[t]hreatening voice messages, windows smashed at home, windows smashed in my car several times and my parents cars on the same day at their home, [and] people following me and sitting outside of my home in Los Angeles for periods of time.”

Rechnitz, who reported the situation to the FBI, suspects Huberfeld orchestrated the actions to deter him from testifying at the upcoming trial, his lawyers write.

“The Government has now confirmed that Jona’s suspicion was correct: the FBI verified, among other things, that the vehicle that had shadowed Jona’s residence was owned by persons with connections to Huberfeld.”

No charges were ever brought.

The letter from Rechnitz’s attorneys follows a glowing submission from prosecutors in which they called him “one of the single most important and prolific” white-collar snitches in recent Manhattan history.

Rechnitz — who pleaded guilty to conspiracy to commit honest services wire fraud — faces a maximum 20 years in prison at sentencing.