One of the top-rated Oscars in recent years lifted ABC to a rare ratings victory last week, as the net finished on top in key demos for the first time since last summer.

As the only Big Four net to not benefit from the National Football League, ABC typically sees its best numbers of the year with the Oscars. And the kudocast came through Sunday, averaging a 13.0 rating/31 share in adults 18-49 and 40.38 million viewers overall — the top-rated entertainment telecast on any net in three years.

(The only downside is that none of the final hour of the Oscars counted in ABC’s averages due to the show’s late start and finish times.)

The net is hoping to parlay its Oscar ratings bounty into tune-in for its entertainment series, including Sunday drama “Red Widow,” which bows this week and was amply promoted during the awards show.

Overall for the week of Feb. 18-24, ABC’s 3.4 rating/9 share was the largest this season for any net that didn’t air major sports. The Alphabet was followed by Fox (2.1/6), CBS (2.0/6), Univision (1.6/5) and NBC (1.2/3).

Univision, which was boosted by its annual “Premio Lo Nuestro” Latin Music Awards, finished ahead of NBC for a fourth straight week and also came to within half a ratings point of both CBS and Fox. And for the February sweep, which ends Wednesday, Univision is projected to finish fourth — its highest finish in any major sweep to date.

CBS, meanwhile, will win in the demo for the first time since 1998. The net aired the Super Bowl, the Grammys and TV’s No. 1 series for the month in “The Big Bang Theory.”

In addition to its breakthrough victory last week in adults 18-49, ABC also won comfortably in adults 25-54 (4.0/10 to 2.9/7 for CBS) and total viewers (11.3 million to 9.6 million).

The net’s week was bookended by first-place finishes, with the Oscars closing things out and “The Bachelor” (3.0/8 in 18-49, 9.26 million viewers overall) and “Castle” (2.3/6, 9.85m) clicking on Monday.

Other standouts for ABC included “Modern Family” (4.0/11, 10.62m), the Thursday combo of “Grey’s Anatomy” (3.1/8, 8.75m) and “Scandal” (2.7/7, 7.68m) and “Shark Tank” (1.9/6, 6.51m). Not so hot were Wednesday’s Katie Couric special on the Oscars (1.3/4 in 18-49, 5.02m) and Thursday’s new drama “Zero Hour” (1.1/3, 5.39m), which was down from its already-soft premiere.

At CBS, “The Big Bang Theory” (5.6/17 in 18-49, 17.62m) ranked as the No. 1 or 2 series for the week in just about every key category — one of 12 series on the net to rank among the week’s top 25 programs in 18-49 — and that’s with the Oscars and its red-carpet pre-shows accounting for four of the slots.

Also of note for CBS was another tick up for Thursday drama “Elementary” (2.4/7, 11.19m), whose solid performance has gotten lost some during the growth spurt for timeslot rival “Scandal” on ABC.

CBS was so dominant in total viewers for the sweep, that it is projected to claim the top 33 telecasts of the month, led last week by “NCIS” (3.5/10, 21.08m).

Fox was paced by “American Idol” on Wednesday (4.1/11 in 18-49, 14.37m) and Thursday (3.9/11, 13.66m), though the show has clearly lost another step this season; there was a time a few years ago when the show was so big that Fox beat ABC during Oscar week.

Also for Fox, “The Following” continues to look good (2.9/7 in 18-49, 8.39m), and Tuesday’s “New Girl” (2.2/6, 4.31m) doubled up competing NBC comedy “Go On” (1.1/3, 3.30m).

NBC should get a boost over the next couple of weeks with the return of “Celebrity Apprentice” and “Grimm,” but it remains very slow going in the meantime. Among its struggling skeins is the Tuesday 9-11 p.m. block of “Go On” (1.1/3 in 18-49, 3.30m), “The New Normal” (0.9/2, 2.80m) and “Smash” (0.9/2, 3.29m) as well as its Thursday lineup, including newbie “1600 Penn” (1.0/3, 2.34m).

There were highs and lows last week for CW, whose Tuesday drama “Cult” bowed to tiny numbers Tuesday (0.3/1, 0.86m). But on Thursday, “The Vampire Diaries” (1.3/4, 2.91m) had its best demos in a while, beating ABC and NBC for the 8 o’clock hour in 18-49.

“The Walking Dead” (5.7/12, 11.02m) dominated cable and edged out “The Big Bang Theory” (5.6/17, 17.62m) among all series for the week in 18-49 — despite taking on the Oscars.

Other top original cable series in 18-49 included AMC’s “The Talking Dead” (1.9/5, 3.50m), Discovery’s “Gold Rush” (1.7/6, 4.46m for its two-hour season finale) and USA’s “WWE Raw” (1.6/5, 4.82m).