The outlet recently revealed the pair hired a popular luxury events planner for the "multi-event" celebrations.
They recruited Colin Cowie - who has organised bashes for Jennifer and Kim Kardashian in the past - to create their second wedding. And his parties can cost anywhere between $25,000 and $25 million.
The guest list is expected to include Ben's brother Casey Affleck, Matt Damon and Jimmy Kimmel.
Lopez, 53, shared details of the Sin City wedding at the late-night drive-thru Little White Wedding Chapel in her On the JLo newsletter, including some pictures and videos of her dress "from an old movie".
In an emotional clip showing off her classic, boat-necked gown, she said: "I've had this dress for so many years, and I've just been saving it, saving it, saving it, and now I'm wearing it on my wedding day."
While at the chapel, Lopez changed into a Zuhair Murad lace off-the-shoulder dress with a corset bodice and fishtail train, as well as a matching veil.
The 50-year-old actor donned a white tuxedo jacket which he hadn't bought especially for the occasion.
Lopez wrote: "So with the best witnesses you could ever imagine, a dress from an old movie and a jacket from Ben's closet, we read our own vows in the little chapel and gave one another the rings we'll wear for the rest of our lives.
"They even had Bluetooth for a (short) march down the aisle. But in the end, it was the best possible wedding we could have imagined. One we dreamed of long ago and one made real (in the eyes of the state, Las Vegas, a pink convertible and one another) at very, very long last."
The 'Shall We Dance' star rekindled her relationship with Affleck back in 2021 after a break of almost 20 years.