In fact, it was Sam’s first public romance since their split from 13 Reasons Why star Brandon Flynn.
“Sam and Christian decided to end their relationship before Christmas,” a source told the Mail.
“They’re still friends and will continue to support each other in their respective careers but for now they have separated.
“Sam has signed back up to dating app Raya and is already connecting with new people… it’s a new year and fresh start for them.”
The Promises hitmaker first met Christian when he collaborated with Sam on the costumes for their music video for I’m Not Here to Make Friends.
As a clothing designer, he’s had plenty of other famous clientele over the years, including A-listers Lady Gaga, Jennifer Lopez, Cardi B and Heidi Klum.
For Valentine’s Day last year, Sam showed their affection for Christian by wearing all items designed by him for his New York Fashion Week show.
Their outfit included a striking red jumpsuit and sequin overcoat they completed with a pair of platform heels.
Sam has also dated model Zeizel, whom they thanked for “breaking their heart” as it scored them four Grammy wins.
Their hit single Stay With Me was written following their split, and Sam promised never to “fall in love again with someone who doesn’t love me back.”
Express.co.uk has approached Sam Smith’s representatives for comment.