The duo reportedly signed their divorce papers and are now just waiting for a judge to sign off to make it official, according to TMZ, which first reported the news.
"It's been over for a while," a source close to Banderas tells PEOPLE. "There's not a lot of drama with the two of them. They're at the point where they can be civil to each other. They're doing this in a healthy way. I know that Antonio is looking forward to the next chapter in his life."
The recent signing took place well after the longtime couple first announced their split in June of last year, issuing a joint statement explaining their decision to end their "almost twenty-year marriage in a loving and friendly manner honoring and respecting each other, our family and friends and the beautiful time we have spent together."
The couple appeared true to their word when they reunited for daughter Stella's high school graduation last month, with Griffith posting several shots of them on Instagram.
"Mama, Stella and Papi," she captioned a photo of the three of them together, a bandage covering the heart-shaped "Antonio" tattoo on her right arm. "Our angel is amazing. Beginning the next chapter of her life! Freedom!!"
Courtesy Melanie Griffith
She also shared a photo of Stella and Banderas together, with the caption "Father and daughter celebrating at Bacclaureate luncheon! So sweet!!"
The friendly images come a year after Griffith requested physical custody of Stella, with visitation for Banderas, in her initial divorce filing. That issue reportedly became moot after Stella turned 18 last September.
This was a fourth marriage for Griffith and a second for Banderas, who in January told a Spanish-language publication the former couple are still on good terms.
"We're going to keep seeing each other," he said. "We will continue. The family isn't dead, not at all."
With reporting by STEVE HELLING