Which late-night TV hosts had the biggest year-over-year ratings gains in 2025?

1. Gutfeld’s breakout: biggest documented year‑over‑year surge

Gutfeld! was the standout in mid‑2025, the only late‑night program that LateNighter reported as growing across both of its primary measures year‑over‑year—up 31.5% in total viewers and up 24% in the 18–49 demo in Q2 2025—making it the single largest documented year‑over‑year gainer in the dataset cited ^[1]. Multiple aggregations of the Q2 numbers repeated that conclusion and noted Gutfeld’s dominance in its slot even as the show dipped versus Q1 2025 (down 9% total viewers and down 22% in the demo quarter‑to‑quarter) ^{[4] [5]}.

2. Kimmel’s steady gains and episodic spikes

Jimmy Kimmel’s show recorded the next most consistent year‑over‑year growth cited in LateNighter’s later monthly tallies: Kimmel posted a 13% gain in total viewers and an 8% rise in the demo in October 2025 according to Nielsen Live+7 data shared by LateNighter, and the same 13%/8% year‑over‑year numbers were repeated in other month‑level reporting ^{[3] [2]}. Those gains appear tied to episodic events—guest lineups, controversy and suspensions—that produced short‑term spikes rather than steady, uniform growth across every quarter ^[2].

3. The Daily Show, Colbert and Fallon: selective upticks

The Daily Show was reported as up roughly 10% year‑over‑year in at least one monthly comparison, while Stephen Colbert posted modest year‑over‑year increases in certain months (e.g., a 7% total‑viewer increase in November reporting) and led the 11:35 p.m. hour in Q2 with strong average audiences (Colbert averaged 2.42 million viewers in Q2 2025) ^{[2] [1] [6]}. Jimmy Fallon’s Tonight Show produced smaller demo gains—about 1% in October—even where total viewers fell, underscoring how different metrics can tell different stories ^[3].

4. Why simple rankings can mislead: different timeframes, metrics and data sources

The “biggest gains” depend heavily on which window and which metric are chosen: LateNighter’s Q2 analysis crowns Gutfeld! the sole cross‑metric grower year‑over‑year, while monthly Nielsen Live+7 breakdowns later in 2025 credit Kimmel and Fallon with year‑over‑year increases in specific months ^{[1] [3]}. Aggregators like Statista and Deseret News echo Colbert’s raw audience lead in Q2, but raw audience size is a different measure than percent growth; the largest percentage gainer was Gutfeld! in the Q2 comparison ^{[6] [1] [7]}.

5. Watch the caveats: partisan commentary and the limits of public reporting

The pieces compiling these numbers include audience commentary and partisan reactions embedded in reporting, which can skew emphasis—several sources include reader or outlet reactions that frame late‑night gains as political victories or losses rather than neutral audience trends ^{[1] [8]}. Also, the publicly available pieces cite Nielsen‑based composites (Live+7) and LateNighter’s tracking; without direct access to the full Nielsen datasets or the complete methodology from every compiler, the published summaries are the best available public evidence but not the raw audit trail ^{[2] [3]}.

6. Bottom line

Using the public 2025 tallies available in these reports, Greg Gutfeld had the largest documented year‑over‑year percentage gains in Q2 2025 (31.5% total viewers, 24% demo) and therefore is the clearest answer to which late‑night host posted the biggest year‑over‑year ratings jump in 2025; Jimmy Kimmel and a few other hosts registered smaller, periodic year‑over‑year gains in later monthly or quarterly snapshots depending on metric and window ^{[1] [3] [2]}.