Months ago, the Rossello administration stopped updating its official death toll at 64 and ordered the independent investigation amid suspicions the dead were substantially undercounted.
Dean of the Milken Institute School, Lynn Goldman, said: "We are hopeful that the government will accept this as an official death toll".
Cars driving through a flooded road in the aftermath of Hurricane Maria in Puerto Rico, on September 2017 (above) and (below) an aerial view of the Roman Baldorioty de Castro highway six months after the passing of Hurricane Maria.
As a result of the study, Puerto Rican Gov. Ricardo Rosselló revised the official death count for the storm from 64 to the study's count of 2,975. In November, a team of demographers at Pennsylvania State University estimated the death count was 1,085.
Researchers found that in the course of this period, poor people and the elderly died at far higher rates than in the years prior.
"That caused a number of issues", Goldman said, adding that people were forced to exert themselves physically or were exposed to intense heat without fans or air conditioning.
That figure was always risible - particularly when you consider that the 150 miles per hour (241 kmh) winds caused around $90bn worth of damage and left households for, on average, 84 days without electricity; 64 days without water and 41 days without cellular telephone coverage.
The disconnect between the administration's initial sanguine assessment of the situation and the enormity of the disaster was evident 12 days into the crisis when Elaine Duke, then acting USA homeland security secretary, characterized the federal response as "a really good news story" and spoke of a "limited number of deaths".
The first phase of the study cost $305,000.
The study said that the risk of dying over this period was 60 percent higher among people living in the poorest areas, the network reported.
Winds lash the coastal city of Fajardo as Hurricane Maria approaches Puerto Rico, on September 19, 2017.
The research represents the most rigorous study of excess mortality due to the hurricane done to date.
Last year's Atlantic hurricane season was a particularly active one.
The new report, though, takes into account an 8 percent drop in the US territory's population after the storm as thousands of survivors left quickly for the mainland.
"I agree that we could be and should be more effective on the operational side ..."
The storm made landfall with winds close to 150 miles per hour (241 km per hour) on September 17 and ploughed a path of destruction across the island, causing property damage estimated at $90 billion and leaving much of the island without electricity for months. Men 65 and older were also found to be at heightened risk.
Rossello pledged to carry out the recommendations, though there are questions about Puerto Rico's ability to do so.