The network gave the Republican 277 electoral college votes to 226 for Democrat Kamala Harris, with 35 results to come.
In the 538 electoral college that will formally elect him, 270 are required to win the presidency.
NBC said that he is winning the race, even though it did not make a formal announcement.
It said that he had reached 266 seats in the electoral college and was likely to pick up at least four more in states where he is leaving.
The announcement came after it and other media declared that he had won Pennsylvania, the crucial swing state needed to win.
The other networks have not yet declared a winner in the bitterly-contested election, although The New York Times estimated that Trump would be getting 306 seats and Harris 232.
The Times estimate was based on analysis based on live poll data and demographic and historical information.
Trump was expected to speak to supporters celebrating his victory at the campaign headquarters in Palm Beach, Florida, where a jubilant crowd was waiting.
Meanwhile, the venue for Vice President Kamala Harris’ victory celebration at Howard University in Washington shut down by 1:30 A.M and her campaign announced that she had gone home.