Kalshi, Polymarket Break Records in $5.9B Week for Prediction Markets

After a busy weekend for NFL trading on Kalshi and Polymarket, both platforms saw week-over-week increases in notional volume to achieve new weekly all-time highs. Top prediction market exchanges overall reached a new high point as well, totaling just shy of $6 billion in notional volume for the week of Jan. 12-18.

Kalshi’s market share was 35.9% to Polymarket’s 29.3% for the week ending Jan. 18. Here’s a look at top-level numbers for the two main prediction market players:

• Kalshi: $2.15 billion (+7.0% WoW)
• Polymarket: $1.76 billion (+16.9% WoW)

Interesting to note that Kalshi is riding a streak of 13 consecutive weeks of outperforming Polymarket on notional volume (since the week of Oct. 20), though a couple of those weeks the two were neck and neck. The last time Polymarket posted higher weekly volume was Oct. 13-19 when Polymarket had $1.06B to Kalshi’s $950.4M.

Kalshi vs. Polymarket volume for the week of Jan. 12-18:

Not included in our Notional Volume dashboard is Opinion, which Dune Data shows a notional volume of $1.94 billion (+21.6% WoW).

A quick look at the trading category data tells us that Kalshi’s lead over Polymarket is primarily driven by the platform’s overall focus on sports. Of Kalshi’s $2.15 billion notional volume last week, a whopping $1.95 billion came from sports. The weekend’s four NFL divisional round playoff games drove a total of $258.8 million in notional volume.

NFL Divisional Round trading volume at Kalshi:

GameDate/TimeTotal VolumeBills at BroncosJan. 17, 4:30 ET$82,591,38849ers at SeahawksJan. 17, 8 ET$69,988,803Texans at PatriotsJan. 18, 3 ET$24,467,389Rams at BearsJan. 18, 6:30 ET$81,774,498

Let’s dig into some of the other data of interest from the past week.

Overall platform comparison (week of Jan. 12-18)

Total notional volume across top prediction market platforms is up 14.5% week over week to $5.99 billion, but note that the platforms which Dune Data is currently tracking have shifted. Dune removed PredictIt from its tracking this week and added predict.fun and ForecastEx.

Top platforms market share for Jan. 12-18

PlatformNotional Volume ($)Market ShareWoW ChangeKalshi$2,153,060,91635.9%+7.0%Opinion$1,941,759,49732.4%+21.6%Polymarket$1,758,081,90529.3%+16.9%predict.fun$113,624,6311.9%—Limitless$18,976,9020.3%+111.6%ForecastEx$5,520,4860.1%—Myriad$2,350,513