Wildlife biologists had to cut away more than 280ft of the commercial fishing line which was being dragged by the whale.
It is now swimming easier than it was, but they had to leave the whale with at least 20ft of the thick rope still tangled in its mouth.
Clay George, a marine mammal biologist with the Georgia Department of Natural Resources, said this would give it "a fighting chance" to free itself.
He said the whale had suffered injuries to its head and tail.
"Disentanglement can't save every whale. The focus must be on prevention."
The team, including members of Florida Fish and Wildlife Conservation Commission, were directed to the whale by an aerial survey team and a satellite tracking buoy monitored by the National Oceanic and Atmospheric Administration (NOAA).
It was initially spotted on near Jacksonville, Florida.
Officials got close enough to cut away most of the rope when it was about 40 miles offshore from Darien, Georgia.
The four-year-old male whale is one of only 450 remaining North Atlantic right whales.
Entanglement in commercial fishing gear is considered one of the leading causes of death and injury and greatest threats to their survival.
More than 80% of North Atlantic right whales bear scars from rope entanglements, and almost 60% have been entangled twice.
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