The British singer, who is recovering from throat surgery and could not attend the Las Vegas ceremony, thanked his fans using flash cards in a surprise video message.
Smith, who won top male artist, top new artist and top radio songs artist at the star-studded show at the MGM Grand Garden Arena, joked that his good friend Taylor Swift should put 100 dollars on black for him.
Swift swept the board at the ceremony, winning in eight of the 14 categories in which she was nominated including fan-voted Billboard chart achievement prize and the night's biggest honour of top artist.
She was seen hugging her new beau Calvin Harris after collecting one of her many awards.
The Scottish DJ was a winner in his own right, collecting the award for top dance/electronic artist.
One Direction came away with two gongs, for top duo/group and top touring artist, dedicating the latter to former bandmate Zayn Malik, who left in March.
Collecting the award from British singer Charli XCX and Victoria's Secret model Lily Aldridge, Liam Payne said: "There one more person to share this with and that is our brother Zayn."
In what was their first awards show appearance as a foursome, Niall Horan also thanked the group's loyal fans, who were rocked by the sudden departure.
He said: "This is absolutely incredible and it's an honour to be here in this category and come out as the winner. Thank you to our super fans, we love you so much and will see you soon."
After scooping his first award of the night Smith appeared in a pre-recorded video and used the flash cards to thank his fans, as well as to send messages to his famous friends.
They read: "Thank you Billboard for this incredible honour. Secondly, thank you to my amazing fans. It's times like this that I realise how lucky I am to have you in my life.
"I can't wait to get this surgery out of the way so I can sing my ass off for you again."
He also instructed Taylor Swift to put 100 dollars (£64) on black for him and told Ed Sheeran he had planned a surprise performance from the Chippendales for him.
The show opened with the debut of Swift's highly anticipated music video for Bad Blood, starring a long cast list of her celebrity friends including Cara Delevingne, Lena Dunham, Ellie Goulding, Selena Gomez, Hailee Steinfeld, Karlie Kloss and Cindy Crawford.
The former country singer spoke of her joy at scoring the award for t op Billboard 200 album for her first pop album 1989.
Dressed in a sleek white jumpsuit with cut out panels, she said: "I am so happy to win this for 1989 because I worked with so many amazing people who are so talented and we put it out and you embraced change. I love you so much, more than I will be able to say to you."
Australian rapper Iggy Azalea won top rap song for Fancy, her collaboration with Charli XCX.
Coldplay won in the rock album category for Ghost Stories.
During the show the crowd were treated to a performance of the Simple Minds hit Don't You (Forget About Me) from the film The Breakfast Club, which was released 30 years ago.
In tribute to the late singer Ben E King rock band Imagine Dragons performed Stand By Me to an audience that included the late singer's daughters and granddaughters.
Presenter Ludacris also gave a touching tribute to blues star BB King, who died on Friday.
The show closed with a dramatic performance of new single All Day and 2013 hit Black Skinhead from rapper Kanye West, who was met with a mix of cheers and boos from the crowd in Las Vegas.
The star rapped in silhouette in front of pyrotechnic effects but was largely muted in the American television broadcast.
Smith tweeted: " Wish I could've been there. Thank you all for your love and support."