Fox Intl. has crossed the $1 billion mark in offshore grosses for calendar 2011, marking the third consecutive year in which the studio was the first to reach that milestone.

Fox hit $1 billion thanks to better-than-domestic overseas holiday leftovers like “The Chronicles of Narnia: The Voyage of the Dawn Treader” and “Gulliver’s Travels,” as well as 3D toon “Rio.”

Fox said it reached the mark with grosses through Sunday. No studio is even close to crossing $1 billion domestically — Universal is closest with $484.7 million.

This year is Fox’s eighth straight with at least $1 billion internationally and its 11th year overall. But without last year’s B.O. phenom “Avatar,” it took Fox considerably more time to reach the same milestone than it did in 2010, when it grossed $1 billion in just 30 days.

Still, the studio boasts this year’s highest overseas grosser, with “Rio” expected to cross $300 million internationally this week.

As for Fox’s 2010 holdovers, boffo specialty title “Black Swan” has contributed $191 million to 2011 totals, while “Gulliver’s Travels” and “Chronicles of Narnia” collected $156 million and $115 million this year, respectively. Overall, “Narnia” has cumed $312.6 million; “Gulliver’s Travels,” $194 million.

“We couldn’t be more proud of the Fox Intl. team for once again reaching this milestone first,” said Fox Inl. co-prexies Paul Hanneman and Tomas Jegeus. “Achieving $1 billion in box office this early and with an extremely varied slate is a testament to the hard work and incredible talent of our people.”

Fox hopes its upcoming summer slate, led by tentpoles “X-Men: First Class” on June 3, and “The Rise of the Planet of the Apes,” slated for Aug. 5, will continue to raise the bar.