Polymarket US began processing multi-leg sports contracts on Aug. 5 through an API-only beta that never surfaced in its consumer app. The launch comes 11 weeks after the platform received certification. Separately, Kalshi is reported to be extending maker fees to its own parlay product, though its published fee schedule does not list that change.
An API-Only Start
The beta is accessible only through an API, meaning regular users won't see the new multi-leg contracts in the app. That's a deliberate choice, though the company hasn't said when the feature will appear in the consumer interface. The timing — 11 weeks after certification — suggests a careful rollout, likely to test the mechanics before a wider release.
Multi-leg sports contracts allow bettors to combine several outcomes into a single wager, a product type that's become a battleground in the prediction market space. Polymarket's move puts it in direct competition with Kalshi, which already offers sports-related contracts.
Kalshi's Reported Fee Change
Kalshi has banked $25 million in fees, according to the facts. Now the platform is reportedly extending maker fees to its parlay product. But the published fee schedule doesn't list that change, leaving traders uncertain about whether the new fees are already in effect or still on the way.
The reported move would align Kalshi's parlay pricing with its other products, but without an updated schedule, it's unclear how the fees would be structured. The $25 million in fees suggests the platform has seen meaningful trading volume, and any change to maker fees could affect how active traders use the service.
The Consumer Rollout Question
Polymarket's API-only beta raises a straightforward question: when will multi-leg contracts reach the consumer app? The company hasn't announced a date. For Kalshi, the question is whether the reported fee extension will be formally published — and when.
Both platforms are moving quickly in the sports prediction market, but the details remain in flux. Polymarket's beta is live but hidden from most users. Kalshi's fee change is reported but not documented. Until either company makes a public announcement, traders are left watching the API and the fee schedule for the next signal.
