Philbin died on Saturday, just one month shy of his 89th birthday.
"This past weekend, we lost an absolute legend," said Fallon on his show.
"He could do everything. He could sing, he was funny, really funny, he was an entertainer," he continued. "He would do anything for a laugh. I loved him, my grandparents loved him, they introduced me. He was part of all of our lives. I loved that he never forgot his Irish roots."
"When I started to become famous on 'Saturday Night Live' and people would ask, 'What's it like when people recognize you on the street, I would be like, 'I feel like Regis,' and everyone understood that," said Fallon. "There was no need for explanation. He was the king of New York."
Jimmy went on to say he was "lucky enough" to have Regis as a guest on his show, as well as appear on "Live" as a guest himself -- saying the two "got to know each other pretty well."
"He will be remembered as a genuinely nice person, a funny human, a good husband, father and grandfather," he added. "He always had that smile and when Irish eyes are smiling, they'll steal your heart away. Regis, we'll miss you."
Over on Seth's show, his tribute was short and sweet, calling Philbin "as great a TV host as we're ever likely to see."
Like Fallon, Meyers too said he was "lucky enough to meet Regis a couple of times and it was a delight how he was exactly the same in person as he was on television."
"The most amazing thing about Regis wasn't his contagious enthusiasm, it was how many years he maintained that contagious enthusiasm," he added. "We send condolences to his wife Joy and the rest of his family. Regis will be missed."
While Jimmy Kimmel is taking a break from his nightly talk show, the host did pay tribute to the TV legend on Twitter over the weekend.
"Regis was a great broadcaster, a good friend and a tremendous amount of fun," he tweeted after Philbin's death. "He leaves behind a beautiful family and a TV legacy that will likely go unmatched. Regis, I hope our friend Rickles met you at the pearly gates with open arms and a slew of the insults you loved so much."
To see more touching tributes from Philbin's former cohosts Kelly Ripa and Kathie Lee Gifford -- as well as Hollywood at large, check out the articles below.