Key Facts
—Runoff. Sunday, 25 October 2026. Polls open at 7:00 a.m. ET and close at 4:00 p.m. ET.
—Latest poll. PoderData/Aya, 22 October: Flávio Bolsonaro 51%, Lula 49% of valid votes, within the 1.6-point margin.
—Court order. Brazil’s electoral court gave Meta 24 hours to report on a pro-Lula WhatsApp channel.
—First round. On 4 October Flávio won 47.03% of valid votes and Lula 45.16%.
—Prediction markets. Polymarket gives Flávio 77.1% and Lula 22.5% to win; Kalshi puts a Flávio win by 0–3 points at 36% (23 October 2026, 3:06 a.m. ET).
—Power Index. Brazil ranks 1st of 14 in The Rio Times Latin America Power Index, with 75.0 points (October 2026 edition).
Runoff · Sunday, 25 October
Brazil Runoff 2026: Lula vs Flávio
Date, polls, debates, odds and how the runoff works, updated every day.
Read our Brazil election 2026 runoff guide →
Brazil runoff polls · Polymarket and Kalshi odds · When results come · Brazil election poll data (CSV)
Prediction markets · who wins the runoff
Implied chance of winning Brazil’s presidency on 25 October, from traders’ prices.
Polymarket
Flávio Bolsonaro 77.1% · Lula 22.5% (US$192 million traded)
Kalshi (regulated in the US by the CFTC)
Flávio Bolsonaro 76% · Lula 24%
As of 23 October, 3:20 am ET (08:20 Lisbon), updated every 20 minutes. Prices are bets, not polls, and can move fast.
Why we show this: prediction markets turn real-money bets into a live probability that moves within minutes of the news, which is why investors, campaigns and newsrooms in the United States now follow them closely. We show them next to polls and official results, never instead of them.
Brazil’s runoff campaign closed with markets leaning toward Flávio Bolsonaro, polls showing a dead heat, and the electoral court demanding platform data on a pro-Lula channel.
In Plain English
- Flávio Bolsonaro: Conservative senator from Rio de Janeiro and presidential candidate for the Liberal Party (PL).
- Luiz Inácio Lula da Silva: Incumbent president of Brazil and candidate of the Workers’ Party (PT).
- Superior Electoral Court (TSE): Brazil’s highest electoral authority, responsible for overseeing elections and campaign rules.
- Prediction markets: Platforms where traders bet real money on outcomes, producing live probability estimates.
PoderData Poll Shows a Technical Tie
The latest PoderData/Aya poll, released on Thursday 22 October, puts Flávio at 51% and Lula at 49% of valid votes. With a margin of error of 1.6 percentage points, the race is statistically tied.
The survey interviewed 4,000 voters by telephone across all 27 federal units. It carries TSE registration BR-07926/2026 and a 95% confidence level.
The previous PoderData wave, released on 19 October, had Flávio at 52% and Lula at 48%. The one-point movement in each direction falls within the margin of error.
Court Orders Meta to Report on a Lula Channel
TSE President Kassio Nunes Marques ordered Meta on Thursday 22 October to deliver a technical report within 24 hours on the WhatsApp channel ‘Exército do Lula’ (Lula’s Army). The channel is administered by federal deputy André Janones and has millions of followers.
The order followed a request from Flávio Bolsonaro’s campaign, which alleged coordinated activity and artificial amplification of pro-Lula content. Google and X were also asked to report whether they detected coordinated amplification of specified terms and hashtags between 18 and 20 October.
The order lands three days before the runoff. It asks the platforms for information and does not rule on the allegations.
What Prediction Markets Say
Prediction markets favour Flávio Bolsonaro, but their prices are bets, not polls. Polymarket gave him 77.1% and Lula 22.5% on 23 October at 3:06 a.m. ET, with about US$192 million traded on the winner market.
Kalshi, which is regulated in the US by the CFTC, ran a runoff margin market with 138,815 contracts traded. It priced a Flávio win by 0–3 points at 36%, a Flávio win by 3–6 points at 36% and a Lula win by 0–3 points at 15%.
On Polymarket’s margin market (about US$4.9 million traded), a Flávio win by under four points stood at 41.0% and by four to eight points at 30.5%. The margin markets also treat a close result as the base case.
Why we show this: prediction markets turn real-money bets into a live probability that moves within minutes of the news, which is why investors, campaigns and newsrooms in the United States now follow them closely. We show them next to polls and official results, never instead of them.
What Links These Stories
The stories point to one question: will Sunday’s count match what traders, pollsters and the courts are signalling? The markets lean to Flávio, the poll shows a tie, and the court order adds a late campaign variable.
A finding of coordinated amplification would feed the argument that the playing field is uneven, while a clean report would remove a distraction for the incumbent.
The reports behind this Big Read
What It Means for US Readers
For US investors in Brazilian stocks, bonds or the real, a razor-thin result means extended uncertainty about policy direction. A wider win for either candidate would remove that doubt sooner.
The social media case matters for US platforms operating in Brazil. Meta, Google and X face court-ordered scrutiny just as American companies navigate Brazil’s evolving rules on content moderation and electoral integrity.
What to Watch Next
Watch for the platforms’ reports, due within 24 hours of the 22 October order. Any finding of coordinated amplification could prompt further court action before Sunday’s vote.
Polling stations open on Sunday 25 October at 7:00 a.m. ET and close at 4:00 p.m. ET. Official results come from the TSE after the polls close.
What Is Not Known
The winner remains unknown until votes are counted on 25 October. Betting prices are not polls, and the leading margin bands range from a very narrow Flávio win to a win of several points.
The exact deadline for the platforms’ reports and their compliance status are not established. Nor is it known whether the court will act on the reports before the vote.
Sources
TSE, Superior Electoral Court · Polymarket, Brazil Presidential Election · Kalshi, runoff margin of victory · CNN Brasil, Nunes Marques gives Meta 24 hours · Jovem Pan, order on the Exército do Lula channel · Terra, election polls
This article was produced by The Rio Times’ automated newsroom system. How we use AI · Report an error · Editorial responsibility: Matthias Camenzind, Editor-in-Chief
Frequently Asked Questions
Who is favoured to win Brazil’s runoff?
Prediction markets favour Flávio Bolsonaro, with Polymarket at 77.1%, but the latest PoderData poll shows a statistical tie at 51% to 49%. The race is too close to call.
What did the electoral court order Meta to do?
TSE President Kassio Nunes Marques ordered Meta to report within 24 hours on the ‘Exército do Lula’ WhatsApp channel, after a request from Flávio Bolsonaro’s campaign.
When are Brazil’s runoff results due?
Voting runs on Sunday 25 October from 7:00 a.m. to 4:00 p.m. ET (8:00 a.m. to 5:00 p.m. in Brasília). Official results come from the TSE after the polls close.