Who becomes the next prime minister of Spain, in the only sense this contract pays? Not the person who leads a voting-intention table, and not a caretaker who keeps the chair after the Cortes are dissolved. The Polymarket event resolves to the individual who receives a vote of confidence from the Congress of Deputies and is sworn in at the head of a new government, by 31 March 2028. If nobody qualifies, it resolves to Other. At 07:45 UTC on 6 October 2026 the yes price on Alberto Núñez Feijóo, leader of the Partido Popular, was 79.5 cents, with the bid at 79 cents, the ask at 80, and the last trade at 79. Pedro Sánchez, still prime minister, was marked at 19.45 cents. Santiago Abascal of Vox was at 1.5 cents. Those three prices already use up the book.
That 79.5 cent mark is not an average of the surveys taken before the dissolution. Sigma Dos, for El Mundo, fieldwork 22 September to 1 October, puts the PP on 140 seats and Vox on 63. Together that is 203, twenty-seven above the 176 votes that make an absolute majority of a 350-seat Congress. The CIS September barometer, study 3577, still has the PSOE at 31.0% and the PP at 25.5%. On that sheet PP plus Vox are 42.1% and PSOE plus Sumar plus Podemos are 40.4%, a bloc gap of 1.7 points. The book is not blending those two parliaments. It is pricing the private seat table, and pricing Feijóo rather than Abascal as the person who spends it.
Key facts
- Feijóo yes price 79.5 cents, bid 79 and ask 80, last trade 79, on $194,569 of volume and $104,067 of that in 24 hours. Source: Polymarket gamma API, 6 October 2026, 07:45 UTC.
- Sánchez yes price 19.45 cents, bid 19.4 and ask 19.5, last trade 19.4, on $208,766 of volume. Same source and time.
- Event volume $770,062, 24-hour volume $416,938, liquidity $975,282. The event was open. Same source and time.
- A general election was called for Sunday 29 November 2026, after the head of state was informed. Source: La Moncloa, 5 October 2026.
- Sigma Dos: PP 32.6% and 140 seats, PSOE 25.6% and 103, Vox 18.3% and 63. PP plus Vox is 203 against a 176 line. Source: Sigma Dos, 5 October 2026.
- CIS study 3577: PSOE 31.0%, PP 25.5%, Vox 16.6%, Sumar 5.7%, Podemos 3.7%, from 4,042 interviews. Source: CIS estimation note, September 2026.
- Our fair value on the Feijóo yes is 69%. The traded 79.5 cents sits above it. The weights are a judgment, set out below.
What the contract actually counts
Polymarket's rules are narrower than winning the election. The person must receive a vote of confidence from Congress and be sworn in. A caretaker who never receives that vote does not count. The primary source is official information from the Government of Spain, with a consensus of credible reporting allowed beside it. The deadline is 11:59 p.m. Eastern Time on 31 March 2028. Gamma's end stamp, 03:59 UTC on 1 April 2028, is that same instant on US daylight time.
Article 99 of the Constitution, in the BOE consolidation, says that after each renewal of Congress the King proposes a candidate. An absolute majority invests that candidate on the first ballot. If it fails, the same proposal returns 48 hours later and a simple majority is enough. Two months after the first investiture vote with nobody invested, both chambers are dissolved and another election is called. Article 101 keeps the outgoing government in functions until the new one takes office. That caretaker spell is not a resolution on this contract.
Article 68 sets Congress between 300 and 400 deputies, on a four-year term that ends if the chamber is dissolved. The BOE proclamation of the 23 July 2023 result records 350 seats, and Sigma Dos's October table adds to the same 350. An absolute majority of the members is 176. A November 2026 election falls before that four-year term would have run out.
Sánchez said the date himself. In the English text La Moncloa published on 5 October, marked as a non-official translation edited by the State Secretariat for Communication, he said that after informing the head of state he had called an extraordinary Council of Ministers that morning "to dissolve the General Courts and call a general election for Sunday, 29 November, in accordance with statutory timeframes." The news line said the text would be published the next day in the Official State Gazette. This piece uses the statement. It does not claim to have read the 6 October gazette.
Feijóo answered the same day at the PP's national headquarters. The party site quotes him: "Esto no va sencillamente de que el PP le gane al PSOE; esto va de que España le gane a Sánchez y a lo que representa." Our translation: this is not simply about the PP beating the PSOE; it is about Spain beating Sánchez and what he represents. He is describing a party contest. The contract is a name passing Article 99. A next-prime-minister book in Romania has already shown how a formal path and the traded name can come apart.
A seat lead is not an investiture. In 2023 the PP plus Vox finished at 170 seats, six below 176, and Feijóo did not become prime minister. The certificate is set out with the October table below.
Where the book trades
The board, not a single name, is the page to open first. The Spain prime-minister event on Polymarket listed Feijóo, Sánchez, Abascal and a long tail when gamma was pulled at 07:45 UTC on 6 October. Links to Polymarket are affiliate links, from which The Traders Spread may earn a commission at no cost to you. Recorded volume was $770,062, of which $416,938 had traded in 24 hours. Liquidity was $975,282.
Sixteen named contracts had volume above zero, and their yes prices summed to 101.2 cents. They are separate yes-or-no markets, not slices of one pool, so nothing forces the column to 100. Placeholder rows for unnamed persons were inactive, had no volume, and sat near 50 cents. A 50 cent mark with a zero print is not a live opinion.
Feijóo's contract is the one the 79.5 cent figure belongs to. On the Feijóo yes market the outcome price was 0.795, the bid 0.79, the ask 0.80 and the last trade 0.79. Liquidity on the leg was about $62,382. The feed's one-day price change was +0.02, against -0.0165 on Sánchez. The dissolution was announced on 5 October, so the daily change overlaps the news. The field does not say the news caused it.
| Name | Yes price | Bid / ask | Last trade | Volume | Our fair value |
|---|---|---|---|---|---|
| Alberto Núñez Feijóo | 79.5 cents | 79 / 80 | 79 cents | $194,569 | 69% |
| Pedro Sánchez | 19.45 cents | 19.4 / 19.5 | 19.4 cents | $208,766 | 22% |
| Santiago Abascal | 1.5 cents | 1.3 / 1.7 | 1.8 cents | $102,038 | 3.8% |
| Other names with volume | 0.75 cents combined | see text | 5.2% |
Outcome prices from gamma at 07:45 UTC on 6 October 2026. The fair-value column is the judgment below, not a second market. The chart shows Sánchez at 19.5%.
Sánchez has traded more than Feijóo and is priced as a clear second. The Sánchez yes market showed an outcome price of 0.1945, a bid at 0.194, an ask at 0.195 and a last trade at 0.194. Volume was $208,766, the most of any name, with $155,500 in 24 hours, and liquidity of about $138,290 was deeper than Feijóo's.
Abascal is the test of whether a PP-plus-Vox seat count means a PP prime minister. His outcome price was 1.5 cents, bid 1.3 and ask 1.7, on $102,038 of volume. The last trade, 1.8 cents, is not the mark. At 1.5 cents the book says a right-bloc majority, if it arrives, is unlikely to install the Vox leader. Isabel Díaz Ayuso was at 0.15 cents on $70,052. Yolanda Díaz was at half a cent on $43,713. Every other named contract with volume summed to 0.75 cents.
Two surveys and a certificate
Sigma Dos published the seat table on its own site on 5 October. Fieldwork ran from 22 September to 1 October, mixed telephone and online, 2,116 interviews, stated sampling error ±2.2 points at 95.5% confidence for an even two-way split. Point estimates: PP 32.6% and 140 seats, PSOE 25.6% and 103, Vox 18.3% and 63, Sumar 6.6% and 9, Podemos 3.3% and 2. The published seats sum to 350: PP plus Vox 203, PSOE plus Sumar plus Podemos 114, and 33 on smaller lists. The ±2.2 point line is a vote error, not a seat error.
CIS study 3577 puts the September estimates at PSOE 31.0% (±1.3), PP 25.5% (±1.2), Vox 16.6% (±1.0), Sumar 5.7% (±0.6) and Podemos 3.7% (±0.5), on 4,042 interviews. Sumar's line excludes Podemos. PP plus Vox is 42.1%. The left-hand trio is 40.4%. The right leads by 1.7 points even in the survey that has the PSOE first. Sigma Dos has the same right-hand pair at 50.9% and the same trio at 35.5%, a gap of 15.4 points. Same parties, different parliament.
The CIS note says the figure is a scenario estimate for the interview period, on the Alaminos-Tezanos model, and that it is not prospective. We keep the largest public sample because it disagrees with the private table, and we discount it for that limit.
laSexta on 5 October, citing 40dB for El País and Cadena SER, has the PP at 31.6%, the PSOE at 27.4%, Vox at 18.4%, Sumar at 5.6% and Podemos at 2.7%. PP plus Vox is 50.0% and the left trio is 35.7%, a gap of 14.3 points, with Sigma Dos rather than CIS. No 40dB sample size or seat table appeared in that passage, so the shares do not enter the weights.
Set the 2023 certificate beside the October table and the change is Vox, not the PP. The BOE of 30 August 2023 records PP 137 and Vox 33, together 170, with the PSOE column on 102, PSC-PSOE on 19 and Sumar on 31. Sigma Dos now has PP 140 and Vox 63. The private majority is a Vox doubling plus a handful of PP seats, and those deputies still have to vote for Feijóo. Seat counts against a market price are a familiar split: the seats are a document, and the name on the contract is a further bet.
How 69 percent is built
Fair value gives Sigma Dos weight 0.60 because the fieldwork is later, it runs through 1 October, and it publishes seats. Inside that world Feijóo's conditional probability is 0.85: 203 clears 176 on a first ballot if the 63 Vox deputies vote for him, and the 0.15 haircut covers a failed bargain or a different PP name. The rest of that world is Sánchez 0.10, Abascal 0.03, and anyone else, including no qualifying prime minister, 0.02. Both conditionals are judgments.
CIS gets weight 0.40 because the sample is almost twice as large, and dropping it would make fair value a restatement of one private table. Inside that world Feijóo is 0.45. A 1.7-point bloc lead, with the PSOE still largest and with no seat translation in the note, looks like a fight, not like 203 seats. Sánchez is 0.40, Abascal 0.05, anyone else 0.10.
Feijóo is 0.60 times 0.85, which is 0.51, plus 0.40 times 0.45, which is 0.18. The sum is 0.69. Sánchez is 0.22. Abascal is 0.038. Anyone else is 0.052. The four figures sum to 1. The 5.2% residual is larger than the 0.75 cents on the other live names because it includes a missed deadline, not only Ayuso.
Both surveys closed before the dissolution. A 29 November election lowers the chance that nobody is invested by 31 March 2028, relative to a Cortes that might have run toward summer 2027. It does not close a 10.5 point gap on our weights. Andersson's Sweden price was a heavy favourite marked above the fair value we would sign. Above fair here means 79.5 cents is richer than 69%. It describes the price. It does not tell anyone which side to take.
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What would change this call
The base case is 69% for Feijóo. The yes price, 79.5 cents at 07:45 UTC on 6 October, is above it, so the call on that leg is that the market sits above our fair value. Sánchez at 19.45 cents is a little under our 22%, and Abascal at 1.5 cents is under our 3.8%. Conviction is moderate: the weights are ours, and neither survey was taken after the Cortes were dissolved.
The bull case drops the CIS weight and keeps the 0.85 conditional, so fair value becomes 85%. In that world 79.5 cents is about 5.5 points under fair, and the 27-seat cushion over 176 does the work. A post-announcement survey that still prints PP plus Vox above 200 seats, with a sample and a date, would push us that way. A published 40dB seat table would count. We do not have one.
The bear case keeps the 0.45 conditional and drops the private table. Fair value falls to 45%, and 79.5 cents is about 34.5 points above it. That reading says the market is treating a 1.7-point bloc lead as if it were already a 203-seat majority. A new public estimate that keeps the PSOE first and keeps PP plus Vox under 176 seats would push us there. The 2023 result, 170 seats and no Feijóo premiership, is the precedent that case borrows.
Four facts would move 69% without a new horse race. A public refusal by Vox to invest Feijóo, or a demand that Abascal take the office, cuts the 0.85 conditional, which assumes those 63 votes are available to him. A PP candidacy that is not Feijóo does the same. A failed first investiture starts Article 99's two-month clock and lifts the chance a repeat election misses 31 March 2028, which would push the residual above 5.2%. If the gazette names a Sunday other than 29 November, the timetable here is wrong. We will not invent a seat range from the ±2.2 point line, or average the 42.1% and 50.9% bloc shares into a poll nobody published.
Questions the price keeps raising
When does the market resolve?
The rules set the deadline at 11:59 p.m. Eastern Time on 31 March 2028. Gamma's end stamp is 03:59 UTC on 1 April 2028, the same moment on daylight time. A prime minister invested after the 29 November 2026 election qualifies. So does one invested after a repeat election, if the confidence vote lands before that deadline. The date comes from the market rules, not from a guess about how long coalition talks last.
Does a caretaker Sánchez count as yes?
No. The rules say an interim or caretaker prime minister who does not receive a vote of confidence does not count. Article 101 keeps an outgoing government in functions until the next one takes office. That holding pattern is ordinary. On this book it is not a winning name. Sánchez resolves to yes only if he wins a fresh confidence vote and is sworn in at the head of a new government.
Why is Feijóo at 79.5 cents if CIS has the PSOE ahead?
The contract is an investiture, not a prize for the largest party. CIS study 3577 has the PSOE at 31.0% and the PP at 25.5%, and even there PP plus Vox lead the left-hand trio by 1.7 points. Sigma Dos turns a much wider private gap into 203 seats. The price follows that seat table and then assumes Feijóo, not Abascal, is the name those seats invest.
What is the 69% made of?
It is 60% of an 85% conditional on the Sigma Dos seats, plus 40% of a 45% conditional on the CIS vote shares. Both conditionals, and the split, are desk judgments. Neither pollster printed them. The later survey gets the larger weight because it publishes seats. Drop either input and the fair value moves to 85% or to 45%.
Can more than one yes contract finish in the money?
The event resolves to one person, or to Other if nobody qualifies by the deadline. The names trade as separate markets, so yes prices need not add to 100 cents. On this pull the live names added to 101.2 cents. Inactive placeholder rows near 50 cents, with no volume, are not part of that sum and are not a live price.
This is analysis of a prediction-market price, not a recommendation to take either side of a contract. The 69% fair value is a judgment built from two surveys, the 2023 seat certificate and the investiture rules, and it can be wrong. Contracts can finish at zero. Capital is at risk.