What if Reform UK wins the most seats in the Commons?
Reform UK as largest party prices unfunded tax cuts and a BoE clash — gilts sell off, sterling drops, and the long end steepens on a fiscal-credibility premium. The direct rhyme is the September-2022 Truss mini-budget: 30y gilt yields spiked ~100bp+, GBP hit record lows, and the BoE intervened on LDI. Forward angle: post-2022 LDI buffers are larger, so the pension-margin-call amplification should be smaller, but the term-premium repricing is the same trade.
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The butterfly cascade
How this trigger trickles across markets, left → right — the root shock, its first‑order moves, then the ripple effects. Drag any node; tap a market for its real price history.
Resolution timeline — how this probability is moving
Our model's odds (electric blue) over time vs the market's (Polymarket, amber), from the past toward the 1–3 years horizon. Each dot is a real macro event that nudged the probability — green pushed it up, red pushed it down. Tap a dot for the source. Loading the probability audit trail…
What it would mean
If this plays out, it is a risk-off shock. Reform UK wins most Commons seats, gilts sell off as markets price unfunded tax cuts and BoE clash. The trigger decomposes into signed root‑shocks — Fed policy path ▲ · Risk appetite ▼ — which propagate through our causal graph to the markets below.