Some of our favorite stars celebrate their 40th birthdays in 2021. Join Wonderwall.com as we take a look at which celebrities were born in 1981… starting with this talented British actress… Dec. 28 marks BAFTA and Golden Globe nominee Sienna Miller's 40th birthday.
Keep reading to see more stars who were born in 1981…
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It's been a big year — a huge, happy year — for Britney Spears. The "…Baby One More Time" and "Oops!… I Did It Again" hitmaker got engaged to love Sam Asghari, succeeded in ending the conservatorship that ruled her life for more than 13 years and on Dec. 2, she turned 40!
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Grammy-winning music star Beyonce turned the big 4-0 on Sept. 4. "I've spent so many years trying to better myself and improve whatever I've done that I'm at a point where I no longer need to compete with myself. I have no interest in searching backwards. The past is the past," she told Harper's Bazaar a month before her 40th. "I feel many aspects of that younger, less evolved Beyonce could never f*** with the woman I am today."
Gone are his boy band days! On Jan. 31, "Man of the Woods" hitmaker and father of two Justin Timberlake blew out 40 candles on his birthday cake.
On Oct. 30, businesswoman and former reaity TV star Ivanka Trump — the daughter of former President Donald Trump — celebrated her 40th birthday.
"Today" show host Jenna Bush Hager and twin sister Barbara Bush Coyne — the daughters of former President George W. Bush and former first lady Laura Bush — turned 40 on Nov. 25.
On Feb. 9, Golden Globe-winning actor Tom Hiddleston — who delighted audiences as Loki in the Marvel Cinematic Universe and wowed them as the titular British soldier in "The Night Manager" — turned the big 4-0.
On Dec. 16, "Jessica Jones" and "Breaking Bad" actress Krysten Ritter turned 40.
Happy birthday, Cap! Chris Evans, who famously played Captain America in the Marvel Cinematic Universe, turned 40 on June 13.
Lady Mary from "Downton Abbey" — Emmy-nominated actress Michelle Dockery — turned 40 on Dec. 15.
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Another "Home Improvement" actor — former child star and teen magazine heartthrob Jonathan Taylor Thomas, who's kept a very low profile in recent years — turned 40 on Sept. 8.
On Sept. 21, reality star-turned-designer Nicole Richie — who's father is Lionel Richie — hit the big 4-0.
Grammy-nominated British singer Natasha Bedingfield — the voice behind hits like "These Words" and "Unwritten," which grew even more popular when it became the theme song for the MTV reality show "The Hills" — turned 40 on Nov. 26.
On Nov. 14, Emmy-nominated former "Saturday Night Live" cast member Vanessa Bayer — who made us laugh with her "pretty cool" impressions of Miley Cyrus, Jacob the bar mitzvah boy and more — blew out 40 candles on her birthday cake.
Summer turned 40 in the summer: "The O.C." alum Rachel Bilson was born on Aug. 25.
Former Victoria's Secret Angel Alessandra Ambrosio strutted into her 40s on April 11.
Model and former Victoria's Secret Angel Adriana Lima (cat)walked into her 40s on June 12.
Zara Tindall turned 40 on May 15. The queen's eldest granddaughter, who's an Olympic silver medal-winning equestrian, welcomed her third child in March.
"One Tree Hill" alum Chad Michael Murray, who's more recently popped up as a recurring character on The CW's "Riverdale" and in a few TV movies, stepped into his 40s on Aug. 24.
On Dec. 27, "Lost" and "Roswell" actress Emilie de Ravin joined the 40s club.
Joseph Gordon-Levitt — the talented actor we've loved in everything from "3rd Rock From the Sun" and "(500) Days of Summer" to "Inception," "Looper" and "Snowdown" — celebrated his 40th birthday on Feb. 17.
Tennis great Serena Williams — who holds the record for the most Grand Slam singles titles won during the Open Era with 23 — entered her 40s on Sept. 26.
From "Roseanne" to "The Conners," former child star Michael Fishman has enjoyed an enduring career in entertainment! The actor turned 40 on Oct. 22.
Grammy-winning "American Idol" alum and Academy Award-winning actress Jennifer Hudson joined the 40s club on Sept. 12. She got a pretty great birthday gift too: Days earlier, she won her first Emmy Award (as an executive producer on "Baba Yaga," a virtual reality animated film), which means that J-Hud is just a Tony Award win away from joining the elite EGOT club!
"Homeland" star Rupert Friend — who next appears in Wes Anderson's "The French Dispatch" and on the Disney+ Obi-Wan Kenobi series, which is due in 2022 — celebrated his 40th birthday on Oct. 9.
On Oct. 16, "Grey's Anatomy" and "Private Practice" actress Caterina Scorsone blew out 40 candles on her birthday cake.
"Home Improvement" star Zachery Ty Bryan turned the big 4-0 on Oct. 9.
Oscar winner Rami Malek — who in 2021 will star as the villain in the James Bond film "No Time to Die — celebrated his 40th birthday on May 12.
Actress and The Honest Co. business mogul Jessica Alba turned 40 on April 28.
Russian tennis star Anna Kournikova — who these days is busy raising her three kids with longtime love Enrique Iglesias — turned 40 on June 7.
"Fringe" actor Seth Gabel had a reason to celebrate in 2021: On Oct. 3, Bryce Dallas Howard's husband joined the 40s club!
2021 has been a big year for Christina Milian. Not only did the singer-actress turn 40 on Sept. 26, but she welcomed her third child in the spring.
We love this Gilmore girl! "Gilmore Girls" and "The Handmaid's Tale" actress Alexis Bledel marked her 40th on Sept. 16.
On Oct. 25, "Dallas" and "Desperate Housewives" actor Josh Henderson joined the 40s club.
Let's hope Ben Schwartz didn't get run over by a Lexus like his alter ego, Jean-Ralphio from "Parks and Recreation," on Sept. 15: It's the day the actor turned 40.
Tony Award-winning "Hamilton" star Leslie Odom Jr., who's also a jazz singer, marked his 40th birthday on Aug. 6.
Duchess Meghan — who in June released a bestselling children's book, "The Bench," and welcomed her second child, daughter Lilibet "Lili" Diana, with husband Prince Harry — celebrated her 40th birthday on Aug. 4. To mark the milestone, she launched the 40X40 mentorship. "…For my birthday, I have asked 40 friends, activists, athletes, artists, and world leaders to help kickoff a global effort by contributing 40 minutes of mentorship to support women re-entering the workforce," Meghan wrote on her Archewell website, "to help women regain confidence and rebuild their economic strength" especially due to the coronavirus pandemic.
Duchess Meghan's "Suits" co-star Abigail Spencer — who we also loved on "Mad Men" and "Timeless" — shares a birthday with the royal: Abigail also turned 40 on Aug. 4. "We were born on the same day, hours apart, in the same year … she's a trusted friend and one of the most glorious people I have ever met," Abigail told "Entertainment Tonight."
On Aug. 5, Jesse Williams — who we loved as Dr. Jackson Avery on "Grey's Anatomy" — turned 40.
"Selling Sunset" star Chrishell Stause blew out 40 candles on her birthday cake on July 21.
"The Vampire Diaries" and "Chicago Fire" alum Taylor Kinney turned 40 on July 15.
Dutch actor Michiel Huisman — you know him from acclaimed shows like "Game of Thrones," "Treme" and "Orphan Black" — marked his 40th on July 18.
"Party Down" and "Veronica Mars" actor Ryan Hansen turned 40 on July 5.
"The Real Housewives of Atlanta" star Porsha Williams turned 40 on June 22. To celebrate, she posted a few new sexy bikini photos on Instagram, captioning the hot shots "Hello 40."
The Killers frontman Brandon Flowers turned 40 on June 21.
On June 20, former child star and season 10 "The Voice" winner Alisan Porter — whom you know from movies like "Curly Sue" and "Parenthood" — turned the big 4-0.
Oscar winner Natalie Portman, who's starred in critically acclaimed films including "V for Vendetta," "The Other Boleyn Girl," "Black Swan" and "Jackie," celebrated her 40th birthday on June 9.
"10 Things I Hate About You" actress Larisa Oleynik is not a teen anymore! The "Secret World of Alex Mack" star celebrated her 40th birthday on June 7.
Comedian Amy Schumer turned 40 on June 1. Next up, she'll star on the Hulu comedy series "Life & Beth," which she also created, writes, directs and executive produces.
"Deadpool" and "Silicon Valley" actor T.J. Miller celebrated his 40th birthday on June 4.
Six-time Grammy winner Brandi Carlile celebrated her 40th birthday on June 1.
Anders Holm, who starred on "Workaholics" alongside Blake Anderson and Adam DeVine, joined the 40s club on May 29.
"The Sopranos" alum Jamie-Lynn Sigler celebrated her 40th birthday on May 15.
Meagan Good, who starred in 2011's "Think Like a Man" and 2013's "Anchorman 2: The Legend Continues," turned the big 4-0 on Aug. 8.
Danielle Fishel, who portrayed whiz kid Topanga Lawrence on "Boy Meets World," turned 40 on May 5. She marked her big birthday with a very special announcement: She's pregnant with her second child, a son. "F O R T Y! I've never been more excited or hopeful for the next decade of my life," she captioned an Instagram photo revealing her baby bump. "I had a beautiful childhood, teenage years I still dream about, my 20's were insane (and mostly miserable) and my 30's brought me lows and highs but eventually I leveled out to a place of security. Security in who I am, what I believe, and with whom I want to spend precious time. I couldn't be more grateful to enter my 40's with my amazing husband and son, excitedly expecting the arrival of baby boy #2. My birthday wish is for all of you to tell someone how much you love them and walk through today with more patience than you normally might."
Hayden Christensen — who portrayed Anakin Skywalker in the "Star Wars" prequel trilogy and will return to the role in the upcoming Disney+ Obi-Wan Kenobi series — turned 40 on April 19.
"Downton Abbey" star Allen Leech celebrated his 40th birthday on April 18.
"True Detective" alum Taylor Kitsch had a full heart on April 8: It was the "Friday Night Lights" star's 40th birthday.
Broadway actress Laura Bell Bundy, who originated the role of Elle Woods in the "Legally Blonde" musical, sang her way into her 40s on April 10.
"Boardwalk Empire" star Michael Pitt — who's also known for his work in "Murder by Numbers," "The Dreamers" and "Funny Games" — celebrated his 40th birthday on April 10.
Reality TV star-turned-DJ Paris Hilton blew out 40 candles on her birthday cake on Feb. 17 — just a few days after she and venture capitalist Carter Reum got engaged on a private island while on vacation to celebrate her big birthday.
Bryce Dallas Howard, who earned a Golden Globe nod for her performance in "As You Like It" and battled dinosaurs in the "Jurassic World" franchise, celebrated her 40th birthday on March 2.
On March 28, Julia Stiles — who's been in everything from "10 Things I Hate About You" and "Save the Last Dance" to "Dexter" and the "Bourne Identity" franchise — blew out 40 candles on her birthday cake.
Stephen Amell, who played Oliver Queen aka Green Arrow on The CW's "Arrow" — and will next star on the small-town Georgia wrestling drama series "Heels" — joined the 40s club on May 8.
Grammy-nominated music star Josh Groban turned 40 on Feb. 27.
On March 29, Tony Award-nominated actress Megan Hilty — who's appeared in Broadway musicals like "Wicked," "9 to 5: The Musical" and "Noises Off" and memorably starred on TV's "Smash" — turned the big 4-0.
Broadway and movie star Josh Gad celebrated his milestone 40th birthday on Feb. 23.
Destiny's Child singer Kelly Rowland turned 40 on Feb. 11. To mark the occasion, she debuted a new single, "Black Magic," the night of her milestone birthday. It was a special time for the vocalist for personal reasons too: She welcomed her second child, son Noah, three weeks earlier, and featured him in the song's video.
Emmy-winning "Orange Is the New Black" star Uzo Aduba blew out 40 candles on her birthday cake on Feb. 10.
"The Big Bang Theory" alum Kunal Nayyar celebrated his 40th birthday on April 30.
Alicia Keys — whose latest album, "Alicia," was released in 2020 — celebrated her 40th birthday on Jan. 25.
"Lord of the Rings" star Elijah Wood marked his 40th birthday on Jan. 28.
Another "Suits" star, Patrick J. Adams, turns 40 in 2021: His birthday is on Aug. 27. He welcomed his second child with wife Troian Bellisario just a few weeks before on-screen wife Meghan Markle had her second baby.
"90210" actress Sara Foster celebrated her 40th birthday on Feb. 5.
"This Is Us" star Susan Kelechi Watson celebrates her 40th birthday on Nov. 11.
Pitbull — aka Mr. Worldwide — turned the big 4-0 on Jan. 15.
On Jan. 22, "7th Heaven" alum Beverley Mitchell turned 40.
Tennis legend Roger Federer hits his 40th birthday on Aug. 8.
"Saturday Night Live" alum and "Aladdin" actress Nasim Pedrad — who currently stars on the TBS comedy "Chad" — turns 40 on Nov. 18.
On March 30, "American Housewife" and "Eastbound & Down" actress Katy Mixon blew out 40 candles on her birthday cake.
Emmy-nominated actress Carrie Coon, who you know from projects like "Gone Girl," "Fargo" and "The Leftovers," turned 40 on Jan. 24.
Ben Barnes, who's starred in "The Chronicles of Narnia" film franchise as well as TV shows like "Westworld" and "The Punisher," turns 40 on Aug. 20.
Four-time Grammy nominee Keyshia Cole marks her 40th birthday on Oct. 15.
On Dec. 29 — just two days before New Year's Eve — "Peaky Blinders" actress Charlotte Riley (aka Mrs. Tom Hardy) will walk into her 40s!
Majandra Delfino, who appeared on "Roswell" and CBS's "Friends with Better Lives," marked her milestone 40th birthday on Feb. 20.
On Jan. 26, "Once Upon a Time" alum Colin O'Donoghue celebrated his 40th birthday.
On May 22, WWE wrestler Daniel Bryan (real name: Brian Danielson) — who stars on "Total Bellas" with wife Brie Bella — hits his milestone 40th birthday.
Eliza Coupe, who famously appeared on "Happy Endings," "Scrubs," "Future Man" and "Quantico," turned the big 4-0 on April 6.
When Evanescence frontwoman Amy Lee wakes up on Dec. 13, she'll be 40.
Music and reality star Ray J celebrated his 40th birthday on Jan. 17.
On July 24, Summer Glau — who you know from "Firefly," "Serenity," "Terminator: The Sarah Connor Chronicles," "Arrow" and more — marked her milestone 40th birthday.
"Narcos," "The Fugitive" and "Logan" actor Boyd Holbrook — who's currently shooting "Indiana Jones 5" — marks his milestone 40th birthday on Sept. 1.
On April 2, "One Tree Hill" alum Bethany Joy Lenz joined the 40s club.
English actress Andrea Riseborough turns 40 on Nov. 20.
On Jan. 8, actress Genevieve Padalecki — who's married to "Supernatural" star Jared Padalecki — turned the big 4-0.
"I Wanna Be Bad" songstress Willa Ford — who's now an interior designer — turned 40 on Jan. 22.
My Chemical Romance guitarist Frank Iero has two reasons to celebrate on his birthday this year: He's turning 40, and it happens on Halloween, Oct. 31!
Singer-songwriter Paloma Faith celebrated her 40th birthday on July 21.
On Jan. 5, DJ Deadmau5 celebrated his 40th birthday!