42% — Will Green Party receive at least 5% of the popular vote in the 2026 Holborn and St Pancras by-election Kalshi 42% · 20 contracts · $0 volume · medium confidence Updated 2026-09-07 12:10:05 UTC Why this matters: This probability reflects traders' assessment that the Green Party will secure at least 5% of the vote share in the Holborn and St Pancras by-election. The 40% odds suggest meaningful uncertainty about Green performance, likely driven by the party's historical vote share in this particular constituency and broader national polling trends. The contract ladder shows traders assign substantially lower probability to higher thresholds—the 10% barrier sits at 72¢ while 25% drops to just 15¢—indicating a consensus view that Green will most likely finish between 5-10%. The upcoming by-election result will definitively resolve this, with the winner and vote totals determined on polling day. Current trading volume is low, suggesting limited market confidence in price discovery. Key factors: - Green Party's performance in the 2024 general election in Holborn and St Pancras relative to the 5% threshold - Current national polling for the Green Party and their trajectory in recent months - Candidate quality and campaign intensity specific to this by-election compared to typical contests - Local demographic and political composition of the Holborn and St Pancras constituency - Turnout patterns in recent by-elections and whether they typically favor or disadvantage minor parties like the Greens Contracts: - Will Green Party receive at least 10% of the popular vote in the 2026 Holborn and St Pancras by-election?: At least 10% — 90¢ Kalshi $0 (weight 5%) - Will Green Party receive at least 15% of the popular vote in the 2026 Holborn and St Pancras by-election?: At least 15% — 88¢ Kalshi $0 (weight 5%) - Will Green Party receive at least 20% of the popular vote in the 2026 Holborn and St Pancras by-election?: At least 20% — 74¢ Kalshi $0 (weight 5%) - Will Green Party receive at least 25% of the popular vote in the 2026 Holborn and St Pancras by-election?: At least 25% — 63¢ Kalshi $0 (weight 5%) - Will Green Party receive at least 30% of the popular vote in the 2026 Holborn and St Pancras by-election?: At least 30% — 40¢ Kalshi $0 (weight 5%) - Will Green Party receive at least 35% of the popular vote in the 2026 Holborn and St Pancras by-election?: At least 35% — 27¢ Kalshi $0 (weight 5%) - Will Green Party receive at least 40% of the popular vote in the 2026 Holborn and St Pancras by-election?: At least 40% — 13¢ Kalshi $0 (weight 5%) - Will Green Party receive at least 5% of the popular vote in the 2026 Holborn and St Pancras by-election?: At least 5% — 94¢ Kalshi $0 (weight 5%) - ... and 12 more --- ## 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. --- *Last verified: 2026-09-07T11:21:05.470Z* By SimpleFunctions — https://simplefunctions.dev/ Cite as: "42% per prediction markets (SimpleFunctions, September 2026)" Canonical: https://simplefunctions.dev/answer/holbornvote Full data: https://simplefunctions.dev/api/public/query?q=Will%20Green%20Party%20receive%20at%20least%205%25%20of%20the%20popular%20vote%20in%20the%202026%20Holborn%20and%20St%20Pancras%20by-election Provider: SimpleFunctions — https://simplefunctions.dev