2026 U.S. Open: To Make the Cut

Platform comparison

Active sub-markets

Market context

The U.S. Open is at Shinnecock Hills, and the cut has already been set at four over after Friday’s second round, with 72 players into the weekend and 84 out. That matters for this market because, in the real event, the binary outcome is no longer an abstract pre-event probability: once a player is below the number and remaining holes are insufficient, the contract effectively resolves towards **No** on a live basis.[1][2]

For comparison with platforms, Polymarket typically shows a raw crowd-implied probability, so a 0% YES reading can look harsher than venue pricing even when the event is still mathematically alive. Kalshi and Betfair usually express the same idea differently, via decimal-style prices or contract prices that need converting into implied probability, while Smarkets quotes in percentage terms but charges commission on winnings rather than embedding spread in the headline price; on a golf cut market, those presentation and fee differences can make identical views look quite different. Historically, U.S. Open cut markets have been sensitive to wind, firmness and the late-Friday cut line, and DataGolf’s pre-cut modelling on this championship pointed heavily towards a 4-over line, which is exactly where the tournament has landed.[1][6]

The main catalyst now is simply whether the listed player can still finish at or above the cut threshold before play closes out, alongside any official score corrections from the USGA and any weather-related interruption to Saturday’s schedule. The tournament is officially scheduled for June 18-21 at Shinnecock Hills, so there is little time left for score movement; traders on Kalshi or Betfair also need to factor in KYC access and settlement rules, while Polymarket’s crowd price can move faster but may sit further from exchange-style liquidity when a player is already several shots behind.[2][4]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We read 2026 U.S. Open: To Make the Cut from four platform perspectives: Polymarket (on-chain CLOB), Kalshi (CFTC-regulated exchange), Betfair Exchange (sports book exchange), Smarkets (peer-to-peer betting exchange). Polymarket's live quote comes directly from the Polygon order book; the other three are listed with their platform attributes — fees, KYC, settlement currency, payment options — because a 1:1 contract comparison without API access would be guesswork.

Resolution & payout

Settlement is the biggest difference between the four platforms: Polymarket on-chain in USDC (instant), Kalshi USD via CFTC (T+1), Betfair and Smarkets in local currency via bank withdrawal (T+1 to T+3). Kalshi Alternative UK routes every trade directly into Polymarket's on-chain settlement, which is why payouts land fastest.

FAQ

Where can I trade this market with the lowest fees?

On Kalshi Alternative UK, which mirrors the Polymarket order book at 0% fees. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

Is this market available outside the US?

Kalshi Alternative UK is available in most jurisdictions where Polymarket isn't directly accessible. Polymarket itself is geo-blocked in the US/UK/EU. Always check local regulations.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.

Do I need to KYC for this market?

Not under $1,500 of lifetime trading volume. Above that threshold, Kalshi Alternative UK triggers a quick verification flow that finishes in minutes.