referendum night, 2016, and what a gap looks like
Posted: Fri Oct 30, 2026 11:13 am
Late on 23 June 2016, the UK voted on EU membership. Early in the evening, polls and commentary pointed to Remain, and sterling climbed. Then results started arriving, and the picture flipped. By the early hours the pound had one of its largest single-day drops on record, falling roughly ten percent at the extremes against the dollar on some feeds.
This was a classic event gap. Price didn't glide down. It jumped from level to level, with few trades in between. Anyone with a stop in the way got filled far from the order, and many market makers widened spreads dramatically or went quiet.
The important point is that the event was scheduled. Everybody knew the date. Still, nobody could hedge the outcome fully, because the market's expectation was lopsided and the reaction was out of proportion to the forecast.
A few things stood out about market behaviour that night:
- Spreads on GBP pairs widened to many times their normal size.
- Some brokers raised margin requirements ahead of the vote.
- Liquidity thinned in Asia, when the reaction continued into the next session.
Referendums and elections differ from data releases because the outcome is binary and the information arrives in pieces over hours. Price can swing back and forth as each constituency reports, and a scalper's stop is far less reliable in that environment.
Some traders sat the night out entirely, and others took positions with tiny size. Both approaches can be defended.
Does anyone remember what their platform showed that night, and how wide did the spread on GBP/USD get on your feed?
This was a classic event gap. Price didn't glide down. It jumped from level to level, with few trades in between. Anyone with a stop in the way got filled far from the order, and many market makers widened spreads dramatically or went quiet.
The important point is that the event was scheduled. Everybody knew the date. Still, nobody could hedge the outcome fully, because the market's expectation was lopsided and the reaction was out of proportion to the forecast.
A few things stood out about market behaviour that night:
- Spreads on GBP pairs widened to many times their normal size.
- Some brokers raised margin requirements ahead of the vote.
- Liquidity thinned in Asia, when the reaction continued into the next session.
Referendums and elections differ from data releases because the outcome is binary and the information arrives in pieces over hours. Price can swing back and forth as each constituency reports, and a scalper's stop is far less reliable in that environment.
Some traders sat the night out entirely, and others took positions with tiny size. Both approaches can be defended.
Does anyone remember what their platform showed that night, and how wide did the spread on GBP/USD get on your feed?