Nearly two-thirds of New York city firefighters and officers who retired last year are collecting pensions of more than $100,000 — in a system that is underfunded, according to a report released Thursday.

“The Fire Department retirement system is financially the least robust of New York City’s five municipal employee pension funds. As of fiscal year 2016, the FDNY funds reported a net liability of $8.9 billion, with financial assets equal to only 57 percent of liabilities,” the study by the Empire Center’s SeeThroughNY website said.

Of the 420 FDNY personnel who retired over the past 12 months, 264 are collecting $100k plus.

And 17 are collecting $200,000 or more.

Many qualified for a higher three-quarters, tax-free disability pension.

Officials said that the 9/11 terror attack on the World Trade Center is still reverberating through the FDNY pension system since Albany approved a law that presumes that firefighters who suffer from cancers or throat, nasal and respiratory illnesses automatically qualify for a disability pension if they were involved in the Ground Zero rescue effort.

The trend of higher disability pension will continue for the foreseeable future because there are still a few thousand FDNY employees who were hired before 9/11, sources said.

Another factor contributing to higher pensions is that the city guarantees a generous 8.25 percent return to FDNY members who voluntarily contribute to a supplemental fund to boost their regular pension.

The deal is so extraordinary that not many firefighters pass it up.

Higher overtime costs are also boosting salaries — and jacking up pensions, said one insider.

Fire Chief John Calderone, a 43-year vet who retired last year, topped the pension list last year with a haul of $272,530.

The average pension was $117,914, down slightly from $120,799 in 2015.

© 2017 New York Post