Jennifer Garner and John Miller first became romantically linked back in 2018 after her divorce from Ben Affleck was finalized

Jennifer Garner is spending quality time with boyfriend John Miller.

On Saturday, the couple was photographed holding hands and smiling while on a walk together in Santa Barbara, Calif. They both sported blue flannels for the sunny outing.

The couple first began dating back in 2018, with a source telling PEOPLE at the time it was “not serious, but she enjoys his company.”

Miller, who is chairman and CEO of Cali Group, owner of the CaliBurger restaurant chain, has two children with his ex-wife, violinist Caroline Campbell. Garner was married to Ben Affleck until the two finalized their divorce in 2018. They share three kids: Violet, 17, Seraphina, 14, and Samuel, 10.

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Jennifer Garner

Jennifer Garner and John Miller. BACKGRID

A source told PEOPLE back in 2018, “Although the divorce was just finalized, Jen has considered herself single for a long time. Dating is just a natural step. Jen will always care about Ben and help him be the best dad. She was very ready to move on though. She seems very excited about the future and is in a great place both personally and professionally.”

Jennifer Garner

John Miller and Jennifer Garner. BACKGRID

Garner and Miller have remained mostly private and have never spoken about their romance publicly, nor have they made any public appearances together.

Garner, 50, told PEOPLE back in March 2021 that she learned a lot about herself during the pandemic: “I’ve learned that I’m pretty sturdy. I’m okay when I’m in the house by myself. I’m okay when it’s just the kids and me. I’m okay when they fall apart. I mean I have my moments, but pretty much, I’m really okay.”

The Adam Project actress added that the idea of getting married again wasn’t an immediate thought.

“I don’t know. I’m so far from it. And I don’t know that marriage would need to be a part… I mean I definitely don’t think that I’ll be single forever,” Garner said at the time. “But this is not the time. I don’t need to complicate it. I’m good.”

Garner will soon be seen in the Apple TV+ series The Last Thing He Told Me.