NYC Mayor Odds: Kalshi & Polymarket Prices Now

Zohran Mamdani won the New York City mayoral election on November 4, 2025, and he's been running City Hall since New Year's Day. If you landed here expecting a live Mamdani-vs-Cuomo-vs-Sliwa scoreboard, that market has already settled — but the mechanics behind it are worth understanding anyway, because prediction markets on this race are still trading, just on different questions.

Mamdani's odds on prediction market Kalshi rose to 98%, while Polymarket showed a 100% chance as the count came in, and he won the November 4, 2025 general election, taking 1,114,184 votes, or 50.78 percent, becoming the first candidate to cross one million votes in a New York City mayoral race since John Lindsay in 1969. Cuomo, running on an independent line after losing the Democratic primary, finished second with 906,614 votes (41.32 percent), and Sliwa came in third with 153,749 votes (7.01 percent).

There is no active "who wins NYC mayor" contract right now — the next general election isn't until 2029. What's still trading is narrower stuff: Polymarket's Mamdani hub currently lists predictions like "Zohran Mamdani out as mayor of NYC before 2027?" alongside a couple dozen other yes/no questions tied to specific policy promises and milestones, not a horse race.

A poll asks a sample of people what they intend to do and extrapolates — a snapshot of stated intent that only updates when the next poll drops. A market price is what traders are willing to pay right now to hold a contract that pays out if a specific outcome happens, and it updates continuously as news breaks. Nate Silver, who advises Polymarket, has pointed out that prediction markets can have some biases toward the types of candidates that free-market, libertarian types like, which is one reason market prices and poll numbers can diverge even when both are working correctly.

In late October, Polymarket posted that Mamdani's odds of victory were collapsing, giving Andrew Cuomo a shot at victory — a claim that struck much of the platform's own community as bewildering, since Mamdani's odds remained above 90%. The post came right as new high-quality polls from Suffolk and Quinnipiac showed Mamdani ahead by "only" 10 points — a real tightening in the polling, but not one that matched the market's brief, dramatic headline.

Under Kalshi's model, users purchase contracts for anything from a penny to 99 cents tied to real-world event outcomes; if the event happens as predicted, the holder is paid $1 per contract, subject to fees. A contract trading at 84 cents implies the market thinks that outcome has roughly an 84% chance of happening. Prices can swing wildly — Mamdani contracts were going for 19 cents five days before the June 24 Democratic primary, then jumped to 49 cents by primary morning.

Three events did most of the work: the primary upset where Mamdani beat Cuomo in June, Eric Adams's withdrawal (Cuomo briefly saw his odds rise to around 16% before most of that bump faded), and the late-campaign polling tightening in late October that rattled the market before Mamdani firmed back up into the low-to-mid 90s heading into election night.

Kalshi is a CFTC-regulated platform available to anyone aged 18 or over in the United States, and its NYC mayor contract drew Mamdani at 84% odds after Adams's exit, on trading volume north of $28 million at that point, climbing far higher by Election Day. Polymarket's total volume for the NYC mayoral election hit $424 million, operating mostly through its international product for most of the cycle rather than a fully domestic one — a jurisdictional wrinkle worth knowing when comparing the two platforms' numbers.

The NYC mayoral race is settled, but the same two platforms are running dozens of other live political and culture contracts right now, priced the exact same way — cents on the dollar, updating in real time.