NCAAB
Jordan Ramsay
March 18, 2025

2025 March Madness Bracket Seeds: Most likely NCAA Tournament first round upsets

It’s the best time of the year for college basketball fans. The NCAA men’s basketball tournament tips-off Tuesday with the First Four, followed by the Round of 32 on Thursday and Friday. The Final Four is set for April 5, setting up the title game on April 7 in San Antonio, Texas.

Before you lock in your brackets, we’ve dived into the numbers to try and pinpoint the most likely first round upsets based on seed history. Do No. 1 seeds have a clean sweep of 16-seeds? Is the 8 vs. 9 matchup a complete tossup? Have 12-seeds really had the edge against 5-seeds?

Let’s find out.

Don’t forget to check out our complete list of March Madness game odds, futures and specials/props.

1 vs. 16

Obviously the 1 vs. 16 seed is the most lopsided in tournament history. No. 1 seeds are 154-2 straight up all-time against 16-seeds, but those two upsets have notably occurred within the last seven years.

In 2018, UMBC shocked Virginia 74-54 as massive 20.5-point underdogs. Keep in mind, the Cavaliers weren’t just a 1-seed, they were the No. 1 overall seed in the tournament.

Most recently, 16-seeded Fairleigh Dickinson stunned No. 1 Purdue 63-58 in 2023, despite a 21-point effort from two-time National Player of the Year, Zach Edey.

That’s where the magic ended for the 16-seeds, as UMBC and Fairleigh Dickinson each lost in the second round.

2 vs. 15

No. 2 seeds are a dominating 145-11 SU all-time against 15-seeds. That stat needs some context, however, as parity in college basketball has really closed the gap between these seeds.

Prior to 2012, No. 2 seeds were only upset four times. But, in recent history No. 15 seeds have won seven times in the last 12 tournaments.

The most recent 15-seed to win was No. 15 Princeton over No. 2 Arizona in 2023. The Tigers entered as 15-point underdogs before they broke brackets everywhere and made a run to the Sweet 16.

Saint Peter’s is the most successful 15-seed in tournament history. In 2022 they shocked a powerhouse Kentucky squad in the first round, eventually becoming the only 15-seeded team to ever reach the Elite Eight.

3 vs. 14

This is one of the matchups where it’s probably better to err on the side of caution. No. 3 seeds have only lost three times since 2016 and they’ve only lost 23 times since 1985.

Overall, 3-seeds are an imposing 133-23 against 14-seeds. When No. 14 seeds manage to win, it tends to be close. Of 23 all-time wins by 14-seeds, 12 games have been decided by three or less points, including six by just one point.

In last year’s tournament, No. 14 Oakland defeated No. 3 Kentucky 80-76. The Golden Grizzlies entered the game as 13.5-point favourites in what became the first big upset of the 2024 tournament.

4 vs. 13

The 4 vs. 13 matchup isn’t the long shot most bettors think it is, with 4-seeds suffering upset losses in 17 of the last 23 tournaments.

Since 1985, No. 4 seeds are 123-33 against No. 13 seeds, but the underdog has historically performed better in tighter matchups. Overall, No. 13 seeds are 7-2 SU against No. 4 seeds in games decided by one point.

Last year, No. 13 Yale took out No. Auburn 78-76 thanks to a crucial block by Samson Aletan in the final four seconds. Tigers entered as 13.5-point underdogs, the largest spread of any of the 4 vs. 13 matchups.

5 vs. 12

This is the money matchup, with at least one 12 seed knocking off a 5-seed in 33 of the last 39 tournaments.

Historically, 12-seeds are 55-101 SU all-time against 5-seeds. Recent history has been even more unpredictable, with three or more 5 vs. 12 upsets occurring in the same tournament five separate times over the last 23 years (2002, 2009, 2013, 2014, 2019).

Last year was a clean split. No. 12 Grand Canyon got by No. 5 Saint Mary’s, 75-66, as a 5.5-point underdog, while No. 12 James Madison slipped by No. 5 Wisconsin, 72-61.

6 vs. 11

Since 1985, No. 6 seeds are 95-61 SU against 11-seeds. Keep in mind, a lot of 11-seeds’ success have come in chunks.

Between 1991 and 1995, 11-seeds went 15-5 SU against 6-seeds and between 2002 and 2004, 11-seeds went 12-4 SU against 6-seeds.

No. 11 seeds opened a new window of success last year, with Oregon, Duquesne and NC State pulling off first-round upsets. The New Mexico Lobos were the only 11-seed to lose to a 6-seed in 2024. NC State actually went all the way to the Final Four, losing to Purdue.

7 vs. 10

Historically, the 7 vs. 10 battle has been very close, with a 10-seed upsetting a 7-seed at least once in almost every March Madness tournament. In fact, No. 7 seeds have only swept 10-seeds twice (1993, 2007) over the last four decades.

Only one 10-seed survived the first round last year, with Colorado State beating Florida 102-100 in a shootout. The year prior, Penn State was the only 10-seed to advance, despite being the largest 10-seed underdog at +2.5 against Texas A&M.

8 vs. 9

The 8 vs. 9 matchup is essentially a tossup and it’s the only seed matchup in March Madness history where the underdog has more wins than the higher seeds, with 9-seeds winning 51.9 per cent of games since 1985.

No. 9 seeds are 81-75 SU against 8-seeds since 1985. Last year, 9-seeds went 3-1 SU and against the spread, with Texas A&M, Northwestern and Michigan State all advancing. TCU beat Utah State 88-72 as the lone 8-seed to survive the first round.