The couple had kept a low-profile at the four-day event. They were pictured watching Trooping the Colour on Thursday and attended a service of Thanksgiving at St Paul's Cathedral on Friday.
WATCH: Inside Prince Harry and Meghan Markle's stunning Montecito home
Having stepped back as working royals, their profile was noticeably scaled back, and there was no sighting of their two children, Archie and Lilibet, during their stay in the UK.
It's thought the Sussexes were driven from their home, Frogmore Cottage, to Farnborough Airport on Sunday morning before departing around 1.30pm. They were then spotted at an airport in Santa Barbara before heading to their Montecito residence.
Harry and Meghan left the UK on Sunday
While it might have come as a surprise that the couple chose to leave the Queen's celebrations early, there was a sign that they were departing before the end of the Jubilee.
Eagle-eyed fans noticed that Meghan's makeup artist, Daniel Martin, shared a farewell post for London on Saturday afternoon.
Prince Harry was pictured back in the States with his family
US-based Daniel, who also did Meghan's makeup on her wedding day, posted a series of snapshots as he thanked the Nomad hotel for their hospitality.
"APPRECIATION POST," he began. "My sincere gratitude to NoMad London for taking incredible care of me while in London the last two weeks.
"From the kind and hospitable team, to the tasty mocktails and dinners - I've found my new home away from home. Looking forward to coming back soon."
Makeup artist Daniel shared a farewell post on Instagram
Daniel and Meghan became friends after meeting while she was filming Suits in 2011. Speaking previously about their friendship, he revealed that Meghan didn't have a publicist at the time, so she had personally reached out to Daniel's agent at The Wall Group when she was in need of a make-up artist. He said they both had an "instant connection".
"I knew what she wanted — it was one of those things where, she looked at herself in the mirror and was like, 'Oh my God, this is what I always wanted, but I didn't know how to get there,'" he told beauty website Into The Gloss.
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