A 6-4 6-3 win over Leylah Fernandez ensured the 18-year-old followed in the footsteps of Virginia Wade, who lifted the Wimbledon trophy in 1977, and she has been backed to win more majors by compatriots Tim Henman and Greg Rusedski.
Raducanu became the first qualifier to ever win a grand slam and was victorious in all 20 sets she played in qualifying and the main draw at Flushing Meadows.
"I send my congratulations to you on your success in winning the United States Open Tennis Championships," a message from The Queen to the teenager read.
"It is a remarkable achievement at such a young age, and is testament to your hard work and dedication.
"I have no doubt your outstanding performance, and that of your opponent, Leylah Fernandez, will inspire the next generation of tennis players. I send my warmest good wishes to you and your many supporters."
Henman, who reached the semi-finals of the US Open in 2004, had been a constant source of support for Raducanu courtside in New York and believes more titles will follow her debut major win.
"What she has achieved, (appearing in a) second grand slam and the way she has gone about it, she will win more of these, she is that good," he told Amazon Prime.
"This is not some flash in the pan or fairy tale. She is playing top-five tennis. Her world will be turned upside-down but she has good people around her and it will be a hell of a ride if she can stay injury-free."
Rusedski was a runner-up at Flushing Meadows in 1997 and, like his fellow Amazon Prime pundit, is sure this is only the start for the player from Kent.
He added: "A star was born tonight. The first set of tennis was the best set of tennis I have seen in a women's final for a long time.
"The future is so bright. She is going to be a multi grand slam winner, a world number one. She is the real deal and it is a breath of fresh air having an 18-year-old win the event."
Britain's Billie Jean King Cup captain Anne Keothavong described Raducanu's victory as one of the greatest ever sporting achievements after she spent 16 months away from the tour until June while she focused on her A-levels.
"It still feels so surreal - that was just an incredible performance from Emma, and from Leylah," she told Amazon Prime.
"A really high-quality tennis match from two teenagers, but honestly I never thought I would see a British female lift a grand slam trophy in my lifetime. I can't put it into words how huge this is.
"This is perhaps one of the greatest sporting achievements ever. I am so happy for her and the way she has done it, to not drop a set in the whole tournament, it is not normal and is unheard of.
"She has the ability to be right up there at the top of the women's game and dominate. Really, the future is looking more than bright."
Keothavong's prediction was echoed by Jo Durie, the last British woman to reach the US Open singles semi-finals in 1983, who described Raducanu as "a smiling assassin".
Durie told BBC Radio 5 Live: "It looks to me like she's a smiling assassin, she's ruthless in the way she goes about her tennis.
"Nobody has really stood apart from anyone else, but Emma Raducanu could be the next one who grabs hold of the opportunity and we've seen her consistency of spirit - feet on the ground, taking it all in her stride.
"All these factors might mean that we see her for many years."
Former Wimbledon junior winner Laura Robson hailed the mentality of the 18-year-old, who will rise to world number 23 in the world having been outside the top-300 before her appearance at the All England Club earlier in the summer.
"What a performance (from) Emma Raducanu, so clutch under pressure. She is just a phenomenal talent," she told BBC Radio 5 Live.
"To deliver that sort of performance today is another level. She is just the full package. Her movement is fantastic, her shots are incredible, the pace and the way she takes it on the rise but for me mentally today she was outstanding."
Prime Minister Boris Johnson paid tribute to Toronto-born Raducanu, he wrote on Twitter: "What a sensational match! Huge congratulations to Emma Raducanu. You showed extraordinary skill, poise and guts and we are all hugely proud of you."
Scotland’s First Minister Nicola Sturgeon also tweeted: “Just incredible! Emma Raducanu is a star, a role model and a champion. Congratulations,” before adding: “Postscript to that final: after the sheer emotion involved in supporting Andy Murray over the years, I can’t be the only one who didn’t expect to feel quite so invested in tennis ever again -
Emma Raducanu has changed that.”
The Duke and Duchess of Cambridge also hailed the achievements of the teenager, who moved to England with her Romanian father and Chinese mother at the age of two.
"Huge congratulations Emma Raducanu on your stunning performances and historic Grand Slam victory!" the Duke and Duchess of Cambridge wrote on Twitter.
"Incredible - we are all so proud of you. Leylah Fernandez well done on your amazing achievements at this year's US Open , it's been a pleasure to watch. C" they added, signing the tweet with an initial from the duchess.
England football captain Harry Kane was quick to pay tribute to Raducanu, tweeting: "Amazing achievement @EmmaRaducanu. Done yourself and the whole country proud. Congratulations!"