It's the most wonderful time of the year! The stars are getting into the holiday spirit, and Wonderwall.com has the pics of your favorite celebs looking a little more jolly than usual… starting with Katy Perry and Orlando Bloom, who dressed up as Mr. and Mrs. Claus to pay a surprise visit to sick kids at Children's Hospital Los Angeles on Dec. 21. Keep reading to see more stars get in the spirit!
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Gwen Stefani, Adrian Young, Tom Dumont and Tony Kanal of No Doubt attended the second day of the 25th Annual KROQ Almost Acoustic Christmas concert at The Forum in Inglewood, California, on Dec. 14.
Reese Witherspoon met Santa at the Tiny Prints Presents The Baby2Baby Snow Day event at The Grove in Los Angeles on Dec. 12.
Mariah Carey flipped the switch to turn the Empire State Building red and green on Dec. 6.
Ice-T and his dog showed off their matching holiday sweaters as part of the CESAR brand's new "Matchy-Matchy" campaign in December.
Camila Alves wore a Christmas sweater with the words "Fleece Navidad" on it at LAX Airport in Los Angeles on Dec. 7.
Christina Hendricks and husband Geoffrey Arend sat on Santa's lap during an evening hosted by Brooks Brothers to celebrate the holidays with St. Jude Children's Research Hospital in New York City on Dec. 13.
Whoopi Goldberg stood outside Lord & Taylor in New York City to show off her exclusive limited-edition holiday sweater collection on Nov. 15.
Neil Patrick Harris gave out Christmas gifts at South Street Seaport in New York City on Dec. 6.
Seth MacFarlane and Lea Michele performed on stage during The Grove Christmas with Seth MacFarlane, presented by Citi, in Los Angeles on Nov. 13.
Kristen Bell and Santa Claus attended The Grove Christmas with Seth MacFarlane, presented by Citi, in Los Angeles on Nov. 13.
Lea Michele and Rachel Platten attended The Grove Christmas with Seth MacFarlane, presented by Citi, in Los Angeles on Nov. 13.
Jane Lynch got Tim Davis and Kate Flannery into the holiday spirit while selling her holiday album "A Swinging Little Christmas" at HSN in St. Petersburg, Florida, in November.
Carmen Baldwin and dad Alec Baldwin attended the Rockefeller Center Christmas tree lighting ceremony in New York City on Nov. 30.
Eva Longoria attended the Winter Wonderland VIP launch in London on Nov. 17.
Sarah McLachlan performed at the Rockefeller Center Christmas tree lighting ceremony in New York City on Nov. 30.
Olivia Newton-John and Santa Claus attended the 85th Annual Hollywood Christmas Parade in Hollywood on Nov. 27.
Whitney Port went to a holiday party with a bottle of Sterling Vineyards Cabernet in early December.
President Obama hugged Santa at the 2016 National Christmas tree lighting ceremony on Dec. 1.
Martha Stewart attended the DailyMail.com and Elite Daily holiday party at Vandal in New York City on Dec. 7.
Elizabeth Hurley and designer Patrick Cox attended the Shepherd Market Christmas lights switch party in London on Dec. 8.
Nolan Gould posed with Santa Claus at the Sixth Annual Holiday Flight for Kids held at Los Angeles International Airport on Dec. 13.
Garth Brooks and Trisha Yearwood performed at the 94th annual national Christmas tree lighting ceremony in Washington on Dec. 1.
Kristin Davis attended the opening of the traditional Christmas market at Gut Aiderbichl animal sanctuary near Salzburg, Austria, on Nov. 10.
Dakota Fanning attended the Holiday Celebration at The Line in New York City on Dec. 14.
Sarah Michelle Gellar posed in front of the Christmas tree at "Hollywood Today Live" on Dec. 12.
Anne Hathaway attended the Winter Wonderland Ball in New York City on Dec. 9.
Simon Cowell and girlfriend Lauren Sliverman enjoyed a night out at Winter Wonderland in London on Nov. 17.
Mariah Carey performed "All I Want for Christmas Is You" in New York City on Dec. 14.
Christie Brinkley and Santa Claus attended the 93rd annual New York Stock Exchange Christmas tree lighting on Dec. 1.
Jaime King posed with Santa at the Not For Sale x Z Shoes Benefit in Los Angeles on Dec. 9.
Beverley Mitchell and husband Michael Cameron brought their children, Hutton and Kenzie, to the Sixth Annual Santa's Secret Workshop event in West Hollywood on Dec. 3.