Isabel Infantes/PA Images via Getty Lily Allen and David Harbour
The "Smile" singer, 35, and Stranger Things actor, 45, obtained a marriage license in Las Vegas on Sept. 6, PEOPLE has confirmed through court records.
While the stars do not appear to have obtained a marriage certificate, Allen and Harbour have one year to officially wed.
A rep for Allen had no comment. A rep for Harbour did not immediately return PEOPLE's request for comment.
In May, Allen showcased what appeared to be an engagement ring in an Instagram post about her "ripped" physique. She seemed to address her sparkler in the comments section.
"First rule of engagement club ........." she wrote after a fan asked her about the diamond. She wasfirst photographed wearing the ring in November.
Stephen Lovekin/WWD/Shutterstock Lily and David
The couple first sparked dating rumors in January, when they attended the BAFTA Tea Party together. Allen revealed in January 2019 that she had split from DJ Meridian Dan, her boyfriend since 2015.
Allen and Harbour were spotted together again in August while he was filming Black Widow in London, where they attended the performance of The Lehman Trilogy and then dined together. Following his hosting debut on Saturday Night Live in October, they were photographed heading to the show’s afterparty in New York City.
Allen appeared to confirm the dating rumors by sharing photos from an SNL sketch, captioning a zoomed-in photo of Harbour's bicep, “Mine.”
James Devaney/Getty Images
At the end of October, Harbour made their relationship social media official by sharing his first-ever Instagram photo of the pair enjoying a day at Disney’s Magic Kingdom in Florida.
“The prince, princess and the parking lot,” he captioned a mirror selfie of the pair. “That seven dwarves mine ride is the best one in the whole damn park. Go on, fight me. #magic #disney #rulebreakers.”
Harbour previously dated Fantastic Beasts star Alison Sudol.
This will be Allen's second marriage. The British pop star wed builder and decorator Sam Cooper in 2011, welcoming two daughters together: Marnie Rose, 7, and Ethel Mary, 8. They announced their split in 2016 before finalizing their divorce in June 2018.