Even though Paramount’s “No Strings Attached” drew an overwhelmingly female-skewed aud, the R-rated romantic comedy managed to buck the genre’s recent trend of modest performers, with a better-than-expected estimated bow of $20.3 million from 3,018 locations.

Pic, toplining Natalie Portman and Ashton Kutcher, saw 70% of its opening gross from femmes, while male auds likely went along for date night, according to a Par exec. Movie’s gender skew was expected, as was its tilt toward the over-25 crowd given the restrictive rating.

“I was always hopeful to get over $20 million, so to do that is a really good thing,” said Par exec VP of distribution Don Harris.

Holiday romantic comedies “How Do You Know” and “Love and Other Drugs” failed to break $10 million during their opening weekends, during their opening weekends, falling behind other broadly playing titles.

Newmarket Films and Exclusive Media Group also launched helmer Peter Weir’s “The Way Back” at 678 locations this weekend with an estimated $1.5 million for a per-screen average of $2,161.

Sony fanboy film “The Green Hornet” held up well, down a reasonable 44%, with an estimated $18.7 million to claim the frame’s No. 2 spot. Last week, the studio pointed to the pic’s sizable Friday-to-Saturday jump as a promising sign for the coming weeks, since adult auds, who typically make up the majority of Saturday grosses, also wait until subsequent frames to visit the multiplexes. “Green Hornet” has cumed $63.4 million.

“The King’s Speech” and “True Grit,” holdovers building momentum in the awards race, continue to perform strongly at the domestic box office.

The Weinstein Co.’s “The King’s Speech,” with an estimated weekend take of $9.2 million, reached $58.6 million domestically, while the tally for Par’s “True Grit” rose to a boffo $138.6 million after an estimated $8 million in its fifth week.

“No Strings Attached” further cements Portman’s recent prowess at the box office, marking the first of five pics in which she’ll appear this year. Fox Searchlight’s 2010 release “Black Swan” continues to see good turnouts coming off Portman’s lead actress Golden Globe.

“Black Swan” posted $6.2 million this weekend, lifting its domestic cume to $83.6 million. The film also kickstarted its international run in nine markets, including Germany, Australia and the U.K., where it started strong with $4.2 million despite competitish from recent phenom “The King’s Speech.”Overall, “Black Swan” grossed $10.9 million internationally, with pic bowing in its next major market, Brazil, on Feb. 4.

“Green Hornet” claimed the weekend’s international B.O. crown, posting $18.7 million in its second outing from 45 markets on 4,775 screens. Oz, with $3.1 million, was the film’s top market, followed by Germany, where the pic earned $2.7 million. Pic’s international totals reached $37.4 million.

Domestic champ “No Strings Attached” received an overall B CinemaScore rating, but moviegoers under 25 appraised the film better with an A-. With the film budgeted at $25 million (before marketing costs), the opening perf puts it in a solid financial position. “We’d like to start like that all the time,” Harris said.

Par expected a launch between $15 million and $18 million for the weekend. The film jumped 13% from Friday to Saturday, but that was expected given its slightly older aud.

“No Strings Attached” tells the story of two friends who start a sex-only affair only to discover the difficulties of keeping love out of the equation. Pic was the second-highest bow for director Ivan Reitman, with “Ghostbusters II” tops at $29.5 million in 1989.

The weekend’s other release, “The Way Back,” is the first title for Wrekin Hill Entertainment, which partnered with Newmarket through a deal with EMG. The film is Weir’s first since 2003 wide release “Master and Commander: The Far Side of the World.”

Pic’s distrib team decided to the launch the film, about a group of Siberian gulag escapees, on Dec. 29 in L.A. for Oscar consideration.

Among the frame’s holdover titles, Universal’s “The Dilemma” had a decent hold in its soph sesh, dropping 45% for an estimated weekend take of $9.7 million, bringing its U.S. totals to $33.4 million.

U’s other comedy offering, “Little Fockers,” continues to play in the top 10, with $4.4 million in its fifth frame for a domestic cume of $141.2 million. Pic has performed nicely Stateside after a so-so Christmas launch.

Likewise, Warner Bros.’ 3D family pic “Yogi Bear” fell just 24% in its sixth frame, coming in above Disney’s “Tron: Legacy,” also in its sixth. “Yogi Bear” grossed an estimated $4.1 million, bringing cume to $88.9 million, while “Tron” reached $163.3 million after earning $3.7 million this weekend.

In limited release, Weinstein’s Ben Affleck starrer “The Company Men” bowed at an aggressive 106 locations with $767,328 and a sturdy per-screen average of $7,239.TWC originally planned a fall 2010 release, but the popularity of Affleck’s earlier release “The Town,” from Warners, may have steered its decision to push back “Company.”

Sony Pictures Classics’ “Barney’s Version” expanded to 16 locations, up from four last weekend, likely motivated by star Paul Giamatti’s Golden Globe win. Pic tallied a robust per-screen average of $10,053, totaling $160,840 in its second frame.