The Guyana government announced at a press conference on Wednesday that the carrier has been approved to fly from Cheddi Jagan International Airport (GEO) following an evaluation by the Guyana Civil Aviation Authority (GCCA).
Fly Jamaica Airways will now launch the routes "as soon as we possibly can", said Captain Lloyd Tai, its chief operating officer.
While the carrier must still secure further approvals, the flights should start "definitely by the end of the year", he told Routes News.
In February, Fly Jamaica started flying between Kingston (KIN) and New York (JFK) four times a week with a B757.
But the carrier is now seeking a second B757, said Captain Tai.
"We are in the market right now sourcing various aircraft," he said.
Fly Jamaica is looking for a plane with the same engine and "same vintage" as its current aircraft, he added.
Toronto and New York are key destinations for the carrier as they are major centres for the diaspora of both Guyana and Jamaica, he said.
The airline is not yet aiming to secure additional destinations, but will start looking as soon as it has established flights from Georgetown, he added.
Jamaica Airways was set up to take advantage of opportunities from "the demise" of Air Jamaica, which was taken over by Caribbean Airlines (CAL) in 2010, said Captain Tai.
CAL, which is scaling back flights to Jamaica, flies from Georgetown to New York (JFK) four times a week and to Toronto (YYZ) twice a week.