The "Hello" crooner posted a selfie of herself dressed for the occasion while watching from home, captioning a touching note in honor of Harry's late mother, Princess Diana, writing, "how happy Princess Diana is upstairs."
The singer, once rumored to be performing at the event, instead watched, celebrated and posted to her Instagram.
With a glass of bubbly raised high, the "Rolling in the Deep" artist, dressed in royal garb, fascinator to boot, continued, "Congratulations Meghan and Harry. You're the most beautiful bride. I can't stop thinking of how happy Princess Diana is upstairs x."
There was also whispers that Adele was to perform at big brother Prince William and Kate Middleton's marriage back in 2011, as well, but she reportedly decided against it.
One for the dress-up fun, Adele celebrated her 30th birthday earlier this month with a "Titanic" themed party in Los Angeles, Calif., where she opted to be Kate Winslet's character, Rose, of course.