Will Flavio Bolsonaro win the most votes in the first round of the 2026 Brazil presidential election?
As of Sep 29, 2026, 4:59 PM ET, Polymarket priced this market at 23.5% (little changed over 24 hours). It had $19.9K traded in the past 24 hours, $132.4K of order-book liquidity and a bid-ask spread of 1.0 pts. probcast.co rates the support behind this price as moderate.
No meaningful repricing — the probability is steady.
The pricing has partial support: healthy trading volume and market depth, a tight spread.
How credible was the move?
Three separate questions — a move can be genuine while the latest price is still settling. Methodology →
Move validity
Is the move backed by real trading and depth?
ModerateThe pricing has partial support: healthy trading volume and market depth, a tight spread.
Consensus stability
Has the market settled at the new probability?
StableThe probability has held near its current level over the past several hours.
Contract clarity
Will the rules resolve without ambiguity?
HighThe resolution rules are relatively specific, with a named source and a defined deadline.
From the latest trade tape (most recent 200 prints) — a live activity sample, not a lifetime total.
What this market actually measures
A presidential election is scheduled to take place in Brazil on October 4, 2026. This market will resolve according to the listed candidate who receives the most valid votes in the first round of this election.
This summary shows the opening of the venue's official rules. ProbCast has not yet generated an independent plain-English interpretation for this contract — review the full rules before relying on it.
View full official resolution rules
A presidential election is scheduled to take place in Brazil on October 4, 2026. This market will resolve according to the listed candidate who receives the most valid votes in the first round of this election. Candidates will be primarily ranked by order of valid votes won. If two or more candidates are tied for any position, ties will be broken by alphabetical order of the candidates’ listed full names as they appear in this market. This market will resolve to the candidate that occupies the highest finishing position after applying this ranking. If the result of this election isn't known definitively by June 30, 2027, 11:59 PM ET, the market will resolve to "Other". This market will resolve based on the result of the election, as indicated by a consensus of credible reporting. If there is ambiguity, this market will resolve based solely on the official results as reported by the Brazilian government, specifically the Superior Electoral Court (Tribunal Superior Eleitoral, TSE) (e.g., https://dadosabertos.tse.jus.br/).
Resolution source: dadosabertos.tse.jus.br
What could move this market next?
- The market's deadline arrivesOctober 4, 2026 at 11:59 PM ET
The contract must resolve based on what has happened by this date.
- Confirmation at the resolution source (dadosabertos.tse.jus.br)
The rules name this source as the basis for settlement.
Derived from the contract's own mechanics as of Sep 29, 5:05 PM ET. ProbCast does not list scheduled meetings, announcements, or data releases it cannot verify.
Advanced analysis (experimental)
Research signals — these models are still accumulating the history needed for full validation, and they can disagree with the headline read. Model confidence: low · expected error ±16 pts.
What's happening
A tight, deep, quote-driven book with little executed flow. The price is stable but reflects resting quotes more than active trading.
- Tight spread on a liquid, calm market
- Deep, balanced resting book
The latest price is a usable but caveated read — weigh it with the market state.
More details — reliability score, dynamics, durability
- Choppy / mean-reverting86%
- Stable consensus5%
- Illiquid / quiet5%
Short-term motion of the price line (~1h), distinct from the environment above — not a prediction of the final outcome.
Secondary read: leaning toward Thin market.
A read-only classification of the market environment — how much weight the current price deserves as a read of consensus. It describes conditions, never a trade.
Market data
24h volume
$19.9K
Liquidity
$132.4K
Total volume
$177.1K
- Category
- Geopolitics
- Venue
- Polymarket
- Open interest
- —
- Spread
- 1.0 pts
- Best bid
- 23.0%
- Best ask
- 24.0%
- Resolves
- Oct 4, 2026
- Resolution
- dadosabertos.tse.jus.br