March Madness Sweet 16 Betting Trends, Stats, Notes: Action Network Betting Primer
We are down to just 16 teams in March Madness now. Entering the First Four, we had nine teams listed under 50-1 to win it all — we still have eight of them left in the field. The best of the best have mainly made it through to the second weekend.
Before we start — it's important to know this is a live-running article. Content, matchups, odds, trends, and systems will all be added to the piece through the end of the Elite 8 on Sunday, March 29 (check the updated as-of date below!).
We're here to answer tourney questions, dish out stats and facts, talk futures, the bracket, coaches, Cinderella, and more. Welcome to the March Madness Sweet 16 edition of Action Network's betting primer.
All data, stats and trends are updated as of Monday, March 23, 1 p.m. ET.
Champs Out
Eye of the Hawk
Iowa upset Florida as a 10.5-point underdog in the Round of 32 to head to the Sweet 16, tied for the biggest upset of this tournament with High Point, which beat Wisconsin in the opening round of the dance.
Double-digit favorites were 46-2 SU in the Round of 32 since 2005 entering the Iowa/Florida game, with 2018 Syracuse being the last team to pull off that upset.
The last time a defending champ lost as a double-digit favorite in the next NCAA Tournament was Duke all the way back in 2002.
Favorites Dominate
Almost 20 Later
In the Round of 64 and 32, closing favorites finished 39-9 SU and 29-19 ATS. The 39-9 SU mark is the fewest underdog outright upsets since 2018 and the T-2nd-fewest in the last 20 years. The 29-19 ATS mark for favorites is the best for any Round of 64 and 32 since 2008.
Favorites of 6 points or more went 27-4 SU and 19-12 ATS in the NCAA Tournament — over the last two years, these big favorites are 59-6 SU and 41-24 ATS entering the Sweet 16 this year.
4+ point favorites are 75-11 SU and 52-34 ATS in the tourney since the start of last year. Top-4 seeds facing a 5 seed or worse in the NCAA Tournament are 60-8 SU and 43-25 ATS, too in that span.
The Longshot Longhorns
Texas To The Bank
From First Four to Sweet 16. Texas beat NC State, BYU and Gonzaga all as underdogs. Here are the other three teams to win as underdogs in First Four, Round of 64 and Round of 32:
2018 Syracuse — lost by 4 in Sweet 16
2013 La Salle — lost by 14 in Sweet 16
2011 VCU — won two more games as dogs en route to Final Four
Texas is the 9th Sweet 16 team to enter the NCAA Tournament with 1000-1 or higher odds to win it all since 1985. The Longhorns had 1,500-1 odds to win it all before the First Four. Here are those teams: 2023 Princeton, 2022 St. Peter's, 2018 Syracuse, 2013 FGCU, 1999 Purdue, 1999 Oklahoma, 1999 Missouri State and 1997 Chattanooga. One made the Elite 8: 2022 St. Peter's.
Sweet 16 Field
Some Long In 'Em
The 16 Sweet 16 teams had combined preseason title odds of +232,650 — which would actually be the 6th-highest mark for any year since 1985, the highest since 2022 and the 4th-highest mark since 2000.
(11) Texas, 1,500-1
(9) Iowa, 250-1
(6) Tennessee, 100-1
(4) Nebraska, 100-1
(4) Alabama, 100-1
A Night To Remember
For The West
High totals and Alabama games aren't a shock. At the moment, this over/under between Alabama and Michigan is 175.5, which would be tied for the highest over/under in an NCAA Tournament game dating back to the end of the 1996 tournament — 30 years.
Since the 1996 tournament, we've had six games with a total of 170+, and five of six have included the Crimson Tide over the last two seasons (2024 and 2025 tournaments).
Cover City
Big Ten On Top
Big Ten is 11-5 ATS in this year's NCAA Tournament, the best mark of any conference. Over the last three years in the NCAA Tournament — 11-5 ATS, 13-8 ATS, 10-6 ATS — the conference 34-19 ATS mark is by far the best mark. During that span, when the Big Ten are favorites in the tournament, they are 27-9 ATS.
The Big Ten has now gone nine straight tournaments .500 ATS or better in the Round of 64, including .500 ATS or better in 14 of the last 15 tournaments.
First Time
Cal's Big Dog
Arkansas is a 9.5-point underdog against Arizona in the Sweet 16. In 85 total NCAA Tournament games, this is John Calipari’s biggest line as an underdog (was +7.5 with UMass in the 1996 Semifinal).
Calipari has been listed as an underdog in the tournament 13 times and is 9-3-1 ATS, going 7-0-1 ATS while with Arkansas and Kentucky and 7-1 ATS as a dog of 4 pts or more in the dance.
Preseason Longshot
All For The Corn
Entering the regular season, Nebraska was 500-1 to win it all and then they entered the field as a 4-seed; now they sit in the Sweet 16.
That is the lowest seed for any Sweet 16 team that entered the season at 500-1 or higher since 2010. Of the 14 previous teams in rhe Sweet 16 who entered year at 500-1 or higher, none were favorites in the Sweet 16 game. The closest comparison was 2018 Clemson as a 5-seed, also 500-1 entering season, lost by 4 pts to 8 seed Kansas.
Quiet on the Western Front
Is This The Year?
Since Arizona won the national title in 1997, no team west of Texas has won it all. We only have one team left in the field that fits this criteria … of course, it's Arizona.
Toyota Times
Home Cooking
Houston plays at the Toyota Center at home in Houston, Texas against Arkansas. The 11th total NCAA Tournament game Houston will play inside the state and fourth in Houston — they are 7-3 SU in Texas and 3-0 SU in Houston.
March Madness 2025
Futures | Matchups | Bet Labs | Trends |
Sweet Sixteen
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Future Markets & Notes
Here's a look at the BetMGM futures market, from opening to current lines to win it all:
What are the highest odds to win the title entering the NCAA Tournament since seeding began in 1978? Only four teams listed above 20-1 entering March Madness have won the title in that same time frame:
2014 Connecticut
100-1 pre-tournament
1985 Villanova
35-1 pre-tournament
2011 Connecticut
25-1 pre-tournament
1983 NC State
25-1 pre-tournament
We still have some longshots left in the field from before the opening round. Here are the longest odds entering the Round of 64 for teams in the Sweet 16:
(11) Texas, 1,500-1
(9) Iowa, 250-1
(6) Tennessee, 100-1
(4) Nebraska, 100-1
(4) Alabama, 100-1
After flip-flopping down the stretch, Michigan overtook Duke to be the favorite to win the NCAA Tournament entering Selection Sunday and then once the bracket came out, Duke moved up to the top spot.
How have pre-tournament favorites performed in March Madness recently? The pre-tournament favorite has gone on to win it all 11 times since 2000, including the last two years, with Florida last year (was tied with Duke at the top) and UConn the year before. That was the first time we've had the pre-tourney favorite win it all in consecutive years since 2017-18.
The pre-tournament favorite hasn't won it all in three straight years since seeding began in 1978 and both Michigan and Duke are still alive entering the Sweet 16.
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How has the preseason favorite to win the national title performed in March Madness?
Purdue
This year's preseason favorite entering the regular season was Purdue, which was +750, with Houston at +900 right behind it. Purdue and Houston were the only two teams listed below 10-1 entering the season and they are both still alive entering the Sweet 16.
In 2021, Baylor and Gonzaga were preseason favorites and met in the title game (Baylor won it all). Prior to that, the last preseason favorite to win it all was North Carolina at +500 back in 2009.
Preseason favorites to make Final Four since 2009:
2021 Baylor
+800 preseason
2021 Gonzaga
+800 preseason
2014/2015 Kentucky
+300/+400 preseason
2009 North Carolina
+500 preseason
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Matchups: Thursday Games
Matt Painter is 28-14 ATS in 42 total games in the NCAA Tournament. Painter is 23-7 ATS in the Round of 64 and 32 and just 5-7 ATS in the Sweet 16 or later.
Since the start of the 2024 NCAA Tournament, Painter and Purdue are 9-0 ATS as a favorite, covering the spread by 7.1 PPG.
Texas is the 6th First Four team to make the Sweet 16:
2026 Texas
2021 UCLA
2018 Syracuse
2014 Tennessee
2013 La Salle
2011 VCU
All five previous teams closed as underdogs, going 3-1-1 ATS. Two closed +6 or higher — 2021 UCLA and 2018 Syracuse, both covered the spread.
Sean Miller has been an underdog in the NCAA Tournament a total of 15 times; his teams are 11-4 ATS in those games, including 3-0 SU/ATS in this year’s tournament.
Nebraska has been dominant against non-conference opponents this season, going 13-0 SU and winning by an average of 17.2 points per game. That includes four games where the Huskers were either underdogs or favored by fewer than five points. Fred Hoiberg’s teams have also performed well historically in March, posting a 34-20-2 ATS record.
Iowa beat Florida as a 10.5-point underdog in the Round of 32. Hawkeyes will be the 7th team since 2002-03 to play a game in the Sweet 16 or later off a double-digit spread upset — those teams are 0-6 SU and 1-5 ATS.
Arkansas is a 9.5-point underdog against Arizona in the Sweet 16. In 85 total NCAA Tournament games, this is John Calipari’s biggest line as an underdog (was +7.5 with UMass in the 1996 Semifinal).
Calipari has been listed as an underdog in the tournament 13 times and is 9-3-1 ATS, going 7-0-1 ATS while with Arkansas and Kentucky and 7-1 ATS as a dog of 4 pts or more in the dance.
Time for Tommy Lloyd to break through? Lloyd has been dominant early in the tournament, going 8-1 SU in the Round of 64 and Round of 32 — he has been to the Sweet 16 three times and is 0-3 SU, losing twice in the round as a favorite.
For Kelvin Sampson, the issues came later in the tournament. Since 2005, he is 13-7 ATS in the Round of 64 and 32, and 4-8 ATS in the Sweet 16 or later.
As a head coach in the NCAA Tournament, Sampson is 22-5 SU as a favorite in Round of 64 and 32. In Sweet 16 or later, he is just 7-5 SU as a favorite.
Since March 1, 2024 — two-plus years — Houston has lost just five games outright when leading at the half (59-5 SU) — all five have come on a neutral court, in 4 of those games, Houston was the pre-game favorite.
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Matchups: Friday Games
Duke has received a one seed 16 times and they have never lost in the first weekend after beating TCU on Saturday. In 8 of the 15 previous tournaments, they made the Final Four.
Duke has also been a strong under team in the NCAA Tournament under Jon Scheyer, with ten of his 13 tournament games finishing under the total. In 15 Duke non-conference games this season, the under is 12-3.
Rick Pitino has been an underdog of 5 pts or more eight times in the NCAA Tournament, and he is 6-2 ATS (pulling the upset three times).
When Pitino is a top-6 seed, he has only closed +6 or higher three times … and he covered all 3 games:
2012 Louisville, Semis
1992 Kentucky, Elite 8
1987 Providence, Sweet 16
When leading at the half in road or neutral-site games, Michigan has won 20 consecutive games outright dating back to February of 2025.
Nate Oats has been particularly strong in high-total environments, going 9-3 ATS in NCAA Tournament games with totals of 155 or higher, compared to 4-7 ATS when totals are lower.
He has also excelled on short rest, which defines the Round of 32. Across his time at Alabama and Buffalo, Oats is 25-13-1 ATS on two days of rest or fewer, including 14-6 ATS in NCAA and conference tournament games.
This week, he has extended his prep to prepare for Michigan. Oats is 33-21-1 ATS as an underdog when playing on 4+ days prep time.
Time to prep has been a good thing for Tom Izzo in the NCAA Tournament. In either the First 4, Round of 64, Sweet 16, or Final Four, Izzo is 30-7 SU and 21-14-2 ATS in his coaching career when listed as a favorite. To be fair, Izzo’s record as a favorite overall in the tournament is just as impressive—he is 47-9 SU and 34-20-2 ATS.
UConn has handled Big Ten competition with ease, going 6-0 SU and ATS against the conference since the start of the 2022 season, beating UCLA also in the Round of 32.
Dan Hurley is 18-4 ATS as a head coach in the NCAA Tournament. He is 8-0 ATS in the Sweet 16 or later, covering the spread by 13.6 PPG in those matchups.
Rick Barnes is trying to start 3-0 ATS in the NCAA Tournament for the 2nd time, doing so back in 2002 with Texas. Barnes has never started an NCAA Tournament, both 3-0 SU and ATS, which he would do by beating Iowa State.
Barnes has coached 16 times in the Sweet 16 or later, going 6-10 SU/ATS in those games. When Barnes’ teams are listed as an underdog in the Sweet 16 or later, they are 0-5 SU and 1-4 ATS.
Iowa State has been great vs. non-conference opponents this season, going 15-0 SU and 9-6 ATS and they are 24-1 SU as favorites in non-conference games over the last two seasons.
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Bet Labs Systems
The old notion, "Fade The Public." This system targets under-bet teams in high-bet games. For this, we are using a 1.1X daily bet average. If you have Bet Labs, increase that DB-AVG for smaller samples, and higher ROI matches.
Current matches: Check updated betting lines. Early on shows Illinois, Duke and Tennessee.
Free-throw shooting in the tournament is key. This system targets the better shooting teams vs. the teams shooting under 75%.
Current matches: Coming Soon!
Over! Look Under.
When two teams that are both over .500 to the over during their season entering the NCAA Tournament meet, the total being inflated and the under hitting has been a good strategy.
Current matches: Purdue/Texas
Market Money
When it comes to the later rounds of the tournament, fade the movement. When the line moves two points or more towards a team (ex. -5 to -7) from opening line to the closing line after the Round of 64, those teams are 9-27 ATS, going 2-15 ATS since the 2013 dance. At the moment, this system fits Florida.
Current matches: Check updated betting lines
Slow It Down
Look for first-half Unders in the NCAA Tournament between slower-paced teams.
Current matches: Houston/Illinois
This system looks to bet against good ATS teams from the season in the NCAA Tournament. It is 15-7 ATS in this year's dance.
Current matches: Coming Soon!
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March Madness Trends
Let's take a live look at the biggest line movements for the Sweet 16 so far.
Biggest Spread Moves
Purdue 1-pt move: -7 to -8 vs. Texas
Rising Totals
Illinois-Houston 1-pt move: 139.5 to 140.5
Michigan State-UConn 1-pt move: 135.5 to 136.5
Tennessee-Iowa State 1-pt move: 137.5 to 138.5
Falling Totals
Texas-Purdue 1-pt move: 149.5 to 148.5
Conference Superlatives
King of Kings
Here are the tournaments trends by conference for this year. The Big Ten and Big 12 lead the way, going 19-7 ATS against all other conferences so far during this year's tournament.
NCAA Tournament trends by conference:
Big Ten: 11-5 ATS
Big 12: 10-4 ATS
SEC: 11-8 ATS
Big East: 2-3 ATS
ACC: 3-9 ATS
(Min. 5 games)
The ACC has played four games as underdogs with just Duke left in the field and those four teams went 0-4 SU/ATS, but losing by ten points or less in all four games.
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Momentum Matters Sometimes
Don't Lose Early
Since seeding began in 1978, every NCAA champion to play in a conference tournament won at least one game in that appetizer for March Madness. In that span, eight champions never actually had a conference tournament ('97 ARI, '95 UCLA, '89 MICH, '87 IU, '81 IU, '79 MSU, '78 UK, '77 MARQ).
If this trend holds true, here are some of the candidates this eliminates this year that is still in the field: Michigan State, Nebraska, Illinois, Alabama.
Exit Soon?
Big Odds
Purdue was 30-1 to win it all entering the tournament as a 2-seed.
Since 1985, we’ve seen 16 top-2 seeds to enter the tournament with future odds of 25-1 or longer — none made the title game, with one making the Final Four, Minnesota back in 1997.
Dog Hunting
Favorites have dominated the NCAA Tournament recently. In the last three tournaments, favorites are 106-80 ATS (57%), covering the spread by 1.4 PPG, with a $100 bettor up 9.3% ROI at +$1,735 — the best three-year stretch for favorites ATS since 2007-09 (110-79-3 ATS, +13.3% ROI).
In that span, favorites of 6+ pts are 46-25 ATS (+$1,712, +24% ROI) and favorites of 8+ pts are 32-14 ATS (+$1,520, +33% ROI).
Cinderella Rollercoaster
Ups and Downs
Iowa beat Florida as a 10.5-pt dog in Round of 32 after High Point did the same to Wisconsin in the Round of 64.
According to our Bet Labs database, after a team pulls off a double-digit point spread upset in the NCAA Tournament, they are 4-21 straight up and 9-16 against the spread in the next round, dating back to 2005.
After pulling the upset in the previous round, teams that get the majority ticket count ATS in their next game are 1-16 SU and 4-13 ATS in this span, with the only win coming from Florida Gulf Coast back in 2013.
Upsets and Betting Records
Heading into the Sweet 16, here are the biggest upsets in the tournament and the betting records set throughout the years.
What is the biggest NCAA Tournament favorite?
In the seeding era, 1999 Duke takes the cake when it was a 46-point favorite against Florida A&M. The Blue Devils beat the Rattlers 99-58, failing to cover the lofty 46-point spread by five points.
This year, Florida closed as a 35.5-pt favorite vs. Prairie View A&M in the Round of 64, which was the biggest NCAA Tournament favorite since that Duke game in 1999.
Biggest Favorites in NCAA Tournament Since 1978:
| Team | Matchup (ET) | Year/Result |
|---|---|---|
| Duke (-46) vs. Florida A&M | 1999, Round of 64 Duke, 99-58 |
 | Kansas (-36.5) vs. Prairie View A&M | 1998, Round of 64 Kansas, 110-52 |
| Kansas (-35.5) vs. Jackson State | 1997, Round of 64 Kansas, 78-64 |
What are the highest & lowest totals in the NCAA Tournament?
The last three years of the NCAA Tournament have changed the game when it comes to totals — and it's all Alabama's fault.
Since the 1996 tournament, we've had six games with a total of 170+, and five of six have included the Crimson Tide over the last two seasons (2024 and 2025 tournaments). Arkansas and High Point in Round of 32 closed with a total of 171.5.
Alabama Last 3 Tournaments
In Alabama's 11 NCAA Tournament games in 2024-26, they are 6-5 to the over, but they are 4-2 to the over with a total of 165 or higher. Here are the highest totals in the last 30 years of the NCAA Tournament:
Prior to Alabama's 2024 and 2025 campaigns, we had only seen two totals since 1995 reach above the 170 mark in the NCAA Tournament, and those came all the way back in 1995, both with Texas involved.
Maryland vs. Texas
O/U: 177
Oregon vs. Texas
O/U: 176
➤In the 1995 tourney, the Texas Longhorns, behind coach Tommy Penders, were averaging almost 93 points per game and had back-to-back games with a total above 170. They faced Oregon in the Round of 64 and won, then the total got a little higher when they faced an even higher-scoring team in Maryland, a game in which the Longhorns lost by 14. Both games went under the total.
Lowest of Low
When it comes to the lowest totals, we've only seen one close below 110, and that came in 1996 between Princeton and Mississippi State. If we lift the floor a bit, we've only seen two totals close at 115 or lower since the 2010 NCAA Tournament — Northern Iowa/Wyoming in 2015 (110.5) and Cal/South Florida in 2012 (114).
Princeton vs. Mississippi State
O/U: 108
➤The story of this over/under tale is Princeton's defense, which was No. 1 in the country in 1995-96 and allowed under 52 points per game. As a 13-seed in the Round of 64, the Tigers beat 4-seed UCLA, 43-41, and held the Bruins to 38.5% shooting (Princeton shot 37% and won). Then, in the Round of 32, the total closed at 108 vs. Mississippi State, which beat Princeton, 63-41, barely staying under the total.
In that span, we've had four totals below 120 points, and they all came back in the 2019 NCAA Tournament:
The lowest total since then was Virginia and Colorado State in 2024 and San Diego State and Creighton in 2022, both with a total of 121.
What are the easiest betting wins in the NCAA Tournament?
Between the moneyline, against the spread and totals, going through history, what have been the easiest (largest margin) wins for bettors? Let's explore.
Easiest Bets Won in NCAA Tournament…
| Teams | Year/Result | Bet Type (Record Since) |
|---|---|---|
 | 2016 National Semifinals Villanova (-2.5) | VIL, 95-51 Covered by 41.5 pts | Against The Spread ('78) |
 | 2026 Round of 64 Florida (-35.5) | UF, 114-55 Won by 59 pts | Moneyline ('78) |
  | 2002 Round of 32 Cincinnati/UCLA (139) | 105-101 Went over by 67 pts | Over ('95) |
 | 2017 Round of 64 S. Dakota St/Gonzaga (157.5) | 66-46 Went under by 45.5 pts | Under ('95) |
What are the biggest betting upsets in the NCAA Tournament?
Since seeding began in 1978, eleven teams have lost straight up in the NCAA Tournament as a favorite of 15 points or more. Let's take a look at the eight who have lost at -17 or higher in that span:
2023
Purdue (-23.5) lost to Fairleigh Dickinson
2012
Missouri (-21) lost to Norfolk State
2018
Virginia (-20.5) lost to UMBC
1997
South Carolina (-18.5) lost to Coppin State
1993
Arizona (-18.5) lost to Santa Clara
2022
Kentucky (-17.5) lost to Saint Peter's
2001
Iowa State (-17.5) lost to Hampton
1986
Notre Dame (-17) lost to Arkansas-Little Rock
➤Since 1978, Kansas has had the most losses by any school as a double-digit favorite (6), but none since 2011. Arizona and Duke are second on that list with four losses as double-digit favorites each — Arizona's last loss came in 2023, while Duke's was back in 2014.
➤Perfect Trip: In that same timeframe, here are the teams with the most SU wins without a loss as a double-digit favorite: Louisville (16-0), Michigan (16-0), Syracuse (12-0), Arkansas (12-0), Maryland (10-0), and UNLV (10-0). Tennessee (9) and Cincinnati (9) are the next-closest teams.
What are the worst betting losses later in March Madness?
Since seeding began in 1978, seven teams have lost straight up in the Sweet 16 or later as a favorite of 10 points or more. Our last example of this came back in 2022 when both Purdue and Gonzaga lost in the same season. Let's take a look at the top seven losses.
2022
Purdue (-13) lost to Saint Peter's
2002
Duke (-12) lost to Indiana
2011
Kansas (-11.5) lost to VCU
1998
Arizona (-10.5) lost to Utah
1997
Kansas (-10.5) lost to Arizona
2022
Gonzaga (-10) lost to Arkansas
1985
