The ceremony was officiated by Millie’s Stranger Thing’s co-star Matthew Modine.
He said: “I have one of the licences to get people married and Millie thought it’d be great and Jake said it’d be a great idea.
“So I wrote the wedding vows, and they loved what I wrote for them to join hands and become husband and wife.”
Speaking last year, the actress revealed she nearly lost her engagement ring out of excitement when Jake proposed.
“He puts the ring on my hand and as I go to show him, the ring falls off my finger [and] plummets – like, so fast, it was like a cinematic movie,” Millie told the The Tonight Show Starring Jimmy Fallon.
“Jake threw himself so deep, the diver was like, ‘You can’t do that! Your ears! Literally, your brain will explode!’
“He throws himself. He does a cinematic grab, opens, and he saved the ring.”