Kalshi processed $3.91 billion in trades on Saturday, setting a single-day volume record, then broke it the very next day with $3.96 billion, according to the exchange's daily market data. The numbers are based on U.S. Eastern days.
What's behind the surge? Parlay-style combos — multi-leg bets that bundle several predictions into one position — accounted for roughly 70% of trading volume on both days. The vast majority of those combos were long shots priced below 1 cent, meaning they had a very low probability of paying out.
The anatomy of a parlay boom
Kalshi's combo feature lets users stack multiple event contracts into a single trade, similar to a parlay in sports betting. The payout multiplies if every leg resolves correctly, but the probability of that happening drops sharply with each added leg. When the individual contracts are already long shots, the combined price can fall below a penny — which is exactly what happened over the weekend.
That structure explains the volume numbers. A trade priced at half a cent still moves a full contract, so even tiny-priced combos rack up notional volume quickly. And because the combos are cheap, traders can take large positions without committing much capital. The result is a feedback loop: more combos create more volume, which sets records, which draws more attention.
Why below-1-cent combos matter
Contracts trading under a cent are essentially lottery tickets. They rarely pay out, but when they do, the return can be enormous. That asymmetry attracts a certain kind of trader — one willing to lose small amounts repeatedly for a shot at a big score. On Kalshi, those trades are now driving the majority of activity.
The exchange doesn't break out how much of that volume comes from unique users or how many of the combos actually resolved in the money. But the concentration in long-shot parlays suggests a retail-driven phenomenon rather than institutional hedging or broad-based event forecasting.
The two-day record streak
Saturday's $3.91 billion was already a record. Sunday's $3.96 billion topped it by roughly $50 million. Both days saw the same 70% combo share, indicating the pattern wasn't a one-off anomaly but a sustained burst of parlay activity.
Kalshi has been pushing its combo product as a way to let users express more nuanced views on interrelated events — for example, combining a Fed rate decision with an inflation print. But the weekend data shows the feature is being used heavily for speculative long shots, not just sophisticated macro bets.
What the exchange hasn't said
Kalshi hasn't issued a statement on the record volumes, and it's unclear whether the surge was tied to a specific event or set of events. The company also doesn't publish a breakdown of combo legs or payout outcomes. What is clear: the exchange's daily volume is now being driven by a product that most traditional market participants would consider highly risky.
The next test comes Monday, when U.S. markets reopen and the weekend's parlay positions begin to resolve. If the combos miss — as their sub-1-cent pricing implies they mostly will — the volume could cool off. If a few long shots hit, the record streak might extend.
