As NBC’s grip on latenight continues to loosen, ABC and CBS enjoyed some milestone achievements during the November sweep.

For the period of Oct. 27-Nov. 3, CBS’ “Late Show with David Letterman” beat NBC’s “The Tonight Show” in adults 18-49 (1.19 million vs. 1.08 million) for its first November sweep victory in the demo since 1994, according to Nielsen. The Eye program also led in adults 25-54 (1.52m vs. 1.40m) while the Peacock institution still held the edge in total viewers (3.65m vs. 3.49m).

Also for CBS, “Late, Late Show with Craig Ferguson” beat NBC’s “Late Night with Jimmy Fallon” in adults 18-49 rating (0.6 to 0.5) — marking the first time in the head-to-head battle (regardless of host) that the CBS show had finished on top in 18-49. “Late Night” prevailed in total viewers (1.73m vs. 1.63m).

At ABC, “Jimmy Kimmel Live” drew its largest audience for any sweeps month to date (1.99 million), including 747,000 in the 18-49 demo. It was the only broadcast talkshow to draw a bigger overall crowd this November vs. last year, rising 7%.

“Kimmel” finished the sweep strong as its Nov. 22 show (on the night of the “Dancing With the Stars” finale) racked up 2.88 million viewers (including 977,000 adults 18-49) for its best numbers on any night since May 24.

ABC’s “Nightline” was November’s top-rated latenight program in 18-49 (1.26 million), 25-54 (1.62m) and total viewers (4.12m). This marks its third straight November sweep victory in 18-49 and total viewers and its second consecutive triumph in 25-54.

NBC’s primetime fortunes are certainly contributing to the net’s declining latenight deliveries among younger viewers. On average among adults 18-49, the net finishes well behind its Big Three rivals in the 10:30 half-hour most, and is most deficient on Monday (with newsmag “Rock Center”) and Thursday (drama “Prime Suspect”).