FIA technical delegate and race director Charlie Whiting conducted a 60-day inspection of the venue that is due to host the race in Austin, Texas, from November 16-18.
Whiting has declared the 5.5km (3.4-mile) track and the pit and paddock buildings as "fantastic", and had no hesitation in awarding COTA 'Grade One' status that now allows it to stage grand prix.
"Everything I've seen so far has been absolutely first class, and the progress that's been made since the last time I was here is amazing," said Whiting in a COTA statement.
"The guys have done an awesome job - it really is quite fantastic! It's built to the highest quality, exactly as we expected, and I've absolutely no complaints whatsoever."
Whiting believes the drivers, in particular, will be impressed given the possibilities available for overtaking, and which are crucial for entertaining an American audience.
Whiting added: "There are three or four corners that are very likely to see overtaking.
"You'll see the turns have been designed so that they're extremely wide and the apex is very short.
"It's a very modern approach to slow corners where we hope overtaking will take place. So I'm very confident it will work well.
"And turn one is awesome! It's the only word I can think of to describe it, and I think drivers and teams coming here for the first time will say the same thing."
Whiting will conduct one final inspection on the Monday before the race to ensure completion of the remaining ongoing landscaping and painting projects.