Highest temperature in Amsterdam on July 21?

Platform comparison

Market context

Amsterdam Airport Schiphol is the reference point for this market, and the payout depends on the **highest recorded temperature** there on 21 July 2026, not the city-wide afternoon average or a daily forecast. The current crowd-implied **0% YES** is best read as a stale pre-settlement artefact rather than a live view of the day’s weather, because the market’s outcome is already determined by the historical observation published on Wunderground’s Schiphol daily record page.

For context, Amsterdam’s summer highs often sit in the low-to-mid 20s Celsius, so the relevant question is usually whether the day reaches a modest warm spell or stays closer to seasonal norms. BBC Weather’s Schiphol page shows **25°C** as a current temperature reading, which is consistent with the sort of level that would place the settlement value in an ordinary summer band rather than an extreme one. On platforms such as Polymarket, Kalshi, Betfair, and Smarkets, the same weather view can be priced differently because some books quote **implied probability**, while others use **decimal odds**; the displayed number is also affected by whether fees are shown upfront, and by who can actually access the market after KYC and jurisdiction checks.

For traders, the main catalysts are the intraday weather developments at Schiphol rather than scheduled announcements: cloud cover, wind direction, showers, and any broader North Sea heat plume can shift the day’s maximum temperature materially. Temperature markets are especially sensitive to airport-specific microclimates, so the airport station matters more than downtown Amsterdam, and late-afternoon readings often decide the settlement range. On comparison platforms, this is the kind of contract where tighter fee structures and faster repricing can matter more than the headline number, because the final outcome is a single observed value rather than a subjective event.

Sources: 1

Methodology

We read Highest temperature in Amsterdam on July 21? 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 mid is the canonical probability; the side-by-side columns benchmark fees, KYC, settlement currency and deposit rails so you can choose the venue that fits your jurisdiction and trade size.

Resolution & payout

Polymarket settles via UMA Optimistic Oracle on Polygon. A proposer posts the outcome with a bond, the two-hour window runs, then the smart contract pays USDC.

Kalshi settles USD through the CFTC-regulated clearinghouse — the cleanest variant, with heavier KYC. Betfair Exchange settles in account currency (GBP/EUR), net of 2-5% commission. Smarkets follows the same model as Betfair with a lower default 2% commission.

FAQ

Polymarket vs Kalshi — which is better?

Depends on your location. Kalshi is CFTC-regulated, US-only with full KYC. Polymarket is global, on-chain, no KYC up to $1,500. Polymarket has ~10x higher liquidity but higher regulatory risk.

Is Betfair a Polymarket alternative?

Only partially. Betfair Exchange is UK-focused with a sports-betting emphasis; they have politics markets but with thinner liquidity than Polymarket. Settlement in GBP/EUR, 2-5% commission on winnings.

What about Smarkets as an alternative?

Smarkets is a UK betting exchange with a lower default commission (2%) than Betfair. Liquidity on political markets is below Polymarket, comparable to Kalshi. Geo-blocked in many jurisdictions.

Which platform is accessible globally?

Polymarket is geo-blocked in the US/UK/EU. Kalshi is US-only. Betfair and Smarkets are UK-restricted. Kalshi Alternative has a different geo footprint and routes to Polymarket's order book at 0% fees.

Are all these platforms regulated?

No. Kalshi is CFTC-regulated (US). Betfair and Smarkets are UK Gambling Commission licensed. Polymarket operates without explicit regulation — a different risk profile than a regulated sportsbook.