81% — Another US government shutdown & House Winner 2026
Leader: Shutdown & Democratic Party at 81% · Polymarket 81% · 2 contracts · $4 volume · low confidence
Updated 2026-06-08 09:28:03 UTC

Tracks the leading outcome in a winner-take-all prediction market set with 2 outcomes.

Why this matters:
This 30% probability reflects the combined forecasts that a US government shutdown will occur before the 2026 midterm elections. The significant 20-percentage-point gap between Kalshi (43%) and Polymarket (23%) suggests disagreement about near-term budget negotiations and fiscal deadlines. Government shutdowns typically occur around funding expiration dates—the next major deadline falls in September 2026. Key drivers include the composition of Congress after the November 2024 elections, the willingness of House leadership to use shutdowns as leverage over spending disputes, and historical patterns of last-minute budget deals. Resolution depends on whether Congress passes continuing resolutions or omnibus spending bills before funding lapses, with late August and September 2026 representing the critical decision period when funding deadlines arrive and brinkmanship typically intensifies.

Key factors:
- Government funding authority expires September 30, 2026—the primary deadline that would trigger a shutdown if Congress fails to act
- Historical shutdown frequency increased during 2015-2019, suggesting political polarization may sustain elevated shutdown risk
- Kalshi's 20-point premium over Polymarket indicates possible differences in how each venue weights recent congressional voting patterns or budget negotiation history
- The current House composition and leadership's fiscal priorities, which would determine willingness to allow a lapse rather than compromise on spending
- Volume concentration in sports contracts rather than political contracts suggests lower overall liquidity and potential pricing inefficiency in the shutdown estimate

Contracts:
- Another US government shutdown & House Winner 2026?: Shutdown & Democratic Party — 81¢ Polymarket $1 (weight 33%)
- Another US government shutdown & House Winner 2026?: Shutdown & Republican Party — 19¢ Polymarket $3 (weight 67%)

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## Methodology

SimpleFunctions aggregates live YES-side prices from Kalshi and Polymarket contracts bound to this question. For binary topics the headline is the liquidity-weighted mid-price (weight = log(1 + 24h volume) × freshness, where freshness is 1.0 if updated <24h, 0.7 if <7d, 0.4 otherwise). For multi-outcome (winner-take-all) topics the headline is the current leader's price — disjoint outcomes are never arithmetically averaged. Snapshots refresh every 5 minutes during market hours.

## SF Signal

- SF Index, regime, and 30d Brier calibration are computed separately and surfaced at https://simplefunctions.dev/admin/calibration.
- No SimpleFunctions index / regime / calibration signal is bound to this topic yet — the headline above is market-derived only.

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*Last verified: 2026-06-08T09:20:08.213Z*

By SimpleFunctions — https://simplefunctions.dev/

Cite as: "81% per prediction markets (SimpleFunctions, June 2026)"
Canonical: https://simplefunctions.dev/answer/another-us-government-shutdown-house-winner
Full data: https://simplefunctions.dev/api/public/query?q=Another%20US%20government%20shutdown%20%26%20House%20Winner%202026
Provider: SimpleFunctions — https://simplefunctions.dev