The fourth time's the charm for Paris Hilton after she said "yes" to her boyfriend, Carter Reum.

After one year of dating, the hotel heiress is now officially off the market after the M13 Ventures founder popped the question during her 40th birthday.

Moreover, the couple reportedly celebrated the blonde beauty's special day on a private island alongside her sister, Nicky.

Paris Hilton, Carter Reum's Engagement

Following this, the "Simple Life" star announced the surprising news on social media as she shared their sweet photo during the engagement.

In a lengthy caption, the soon-to-be bride called her now fiance as her "soulmate," adding, "There's no one I'd rather spend forever with," Paris Hilton's Instagram caption reads.

In another post, the reality star shared that Reum made her "dream come true" and described this as her "best birthday surprise ever!!"

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Paris Hilton's Engagement Ring

The 40-year-old socialite spilled the details regarding her dreamy engagement.

The hotel heiress turned DJ wore a stunning white gown with side slit features.

According to her website, it was a Retrofête's Margarita Dress in Snow White that retails for $1,145.

She then capped off the look with her signature rhinestone fingerless gloves and a crown from Loschy.

As for the main event, Paris Hilton's engagement ring was custom made by the famous Jean Dousset, who is also the great-great-grandson of the iconic French jeweler Louis Cartier.

Interestingly, she revealed on her website that the breathtaking mega-carat sparkler was handcrafted for the socialite and was named "Paris."

"A group of finest diamond cutters, polishers, jewelers, and setters, were assembled for this special project," the statement reads, alongside a photo of the emerald-cut jewelry.

Moreover, she also uploaded a short clip on her Youtube channel as she gets into detail about her massive ring.

A 39-second clip shows how her jaw-dropping engagement ring was conceptualized, drafted, and designed by the renowned jeweler.

As cited by Popsugar, experts estimate that Paris Hilton's engagement ring might cost around $1 to $2.5 million, while the emerald cut diamond ranges from 10 to 15 carats.

On the other hand, E! News noted that WP Diamonds CEO Andrew Brown thinks the ring "appeared to be a 20-carat emerald cut diamond ring with trapezoid diamonds on each side," that would probably retail "for $2 million."

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Paris Hilton's Previous Engagement

As mentioned above, this is not the first time she got engaged.

In 2002, model Jason Shaw, who is eight years her senior, proposed to 21-year-old Hilton; unfortunately, the two called off their plans after being engaged for a year.

Three years later, the "House of Wax" star got engaged for the second time to Paris Latsis--a Greek shipping heir.

Paris Hilton received a 24-carat canary diamond ring valued at $4.7 million; however, things went south when they ended their relationship less than six months later.

Then there was Chris Zylka, whom the socialite dated for two years.

In 2018, "The Leftovers actor" popped the question on New Year's Eve in Aspen, Colorado.

The engagement ring reportedly cost around $2 million and was designed by celebrity jeweler Michael Greene.

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