Mamdani's First 100 Days: What Prediction Markets Are Pricing

Update — August 15, 2026. Reviewed as of this date. The political contracts discussed below remain listed on [Kalshi](=AFF:kalshi) and [Polymarket](=AFF:polymarket); the widget above carries the live price. Polling figures cited in this piece are quoted verbatim from the pollster's own release and are not re-estimated by us.

If the approval-rating piece was the poll read on Mayor Mamdani's first 100 days, this is the market read. Same mayor, different instrument — and on a few questions, a very different number.

Polymarket — out before 2027

~5¢ (≈95% finishes year)

Kalshi — 2029 reelection

Clear favorite, long tail

Rent-freeze contract

Firming into RGB vote

Budget signal

FY2027 vote — late June

Last updated

July 2, 2026

Why a market read, not just a poll read

A 48% approval number tells you how New Yorkers feel today. A reelection price tells you what traders think happens between now and 2029. Both are useful; neither is a prediction. The market just compresses every budget headline, every Rent Guidelines Board vote and every primary-calendar wrinkle into one number that reprices in real time.

The cleanest move of the last month was on Polymarket's "Zohran Mamdani out as mayor of NYC before 2027" contract. It drifted from the mid-teens at inauguration into the single digits as the administration stabilized — the market saying, in plain English, that the political-risk premium has come out.

The four contracts worth watching

• —FY2027 city budget vote (late June). The first hard test of the Mamdani–Council relationship. Watch for a Kalshi event contract on whether the budget passes by the statutory deadline.
• —Rent Guidelines Board — zero-percent vote. The cleanest test of Mamdani's signature housing platform. Both Kalshi and Polymarket list contracts on the RGB outcome.
• —NYPD commissioner retention at year-end. A first-term staffing question that drives the political-risk number. Contract resolves December 31.
• —2029 NYC mayoral reelection. The long-dated forward read. It bakes in everything above and more.

Where the poll and the market disagree

Approval polling has Mamdani in the mid-to-high 40s and stable. The 2029 reelection contract prices him as the clear favorite, but with a wider distribution than a 48% sitting-mayor number usually implies. The gap is the four-year horizon — traders are pricing a city budget cycle, a national midterm, and a Democratic primary calendar that hasn't happened yet.

The other gap: poll samples include people who do not vote. Off-year mayoral-primary turnout in New York is structurally low, which means the market is implicitly weighting Mamdani's actual coalition more heavily than a registered-voter poll does.

How to trade these from New York

Kalshi is CFTC-regulated and available to verified NY residents on every device — promo code NYPREDICTS for a $10 new-trader credit. Polymarket's iOS app is available to verified New York residents — promo code NYPREDICTS for a $50 trading bonus after a $20 deposit. Both have live Mamdani-related contracts as of publication.

Editorial only — not a recommendation to trade. Confirm eligibility on each platform before depositing. For the broader legal picture see our NY legality guide.