The twelfth season of the Argentine version of the television reality show "Gran Hermano" was announced on 3 July 2024 by Telefe, with Santiago del Moro continuing as the show's host.
The show follows a group of contestants (known as HouseGuests), who live in a house together while being constantly filmed and having no communication with the outside world as they compete to win a grand prize. Each week, the HouseGuests compete in a Head of Household (HoH) competition which gives them immunity from nominations and the power to save one of the nominees up for eviction. 
On eviction night, the audience votes to evict one of the nominees.
The season premiered on 2 December 2024, and concluded on 24 June 2025. It is the third continuous season to air on Telefe after making its return to the network in 2022. On 22 June 2025, "Gran Hermano" was renewed by Telefe for a thirteenth season.
Santiago Algorta was crowned the winner of the season, with Ulises Apóstolo finishing as runner-up and Luz Tito in third place.
Format.
The show follows a group of contestants, known as HouseGuests, who live inside a custom-built house outfitted with cameras and microphones recording their every move 24 hours a day. The HouseGuests are sequestered with no contact with the outside world. During their stay, the HouseGuests share their thoughts on their day-to-day lives inside the house in a private room known as the Diary Room. Each week, the HouseGuests compete in competitions to win power and safety inside the house. At the start of each week, the HouseGuests compete in a Head of Household (abbreviated as "HOH") competition. The winner of the HoH competition is immune from eviction and selects another HouseGuest to be saved for eviction. On eviction night, the audience vote to evict one of the nominees, and the nominee with the most votes is evicted from the house.
Format changes and additions.
Head of Household Super Powers.
Beginning this season, the HouseGuest that wins the competition, gets series of Super Powers to use during the week.
The voided votes.
From week 2 onwards, the last evicted HouseGuest has the power to void any of the remaining HouseGuests' votes before they nominate in the Nominations Gala.
The Kiosk.
This season, "Gran Hermano" installed a kiosk where HouseGuests use for special prizes every week.
Red Phone.
Starting in Week 6, "Gran Hermano" enabled the red phone. Whoever answered the phone would receive positive or negative information. The HouseGuests must answer the phone without being able to repeat it during the day and if the phone is not answered before five rings the whole house would be punished.
Repechage.
In Week 6, after Andrea walked from the game for health reasons, it was announced that a repechage would take place among the first seven evictees during Week 7. As Keila was ejected from the game, she was ineligible to take part in the repechage. In Week 9, it was announced that the second repechage would take place during Week 10. The second repechage had two stages with the three HouseGuests with the most votes from the public were eligible for re-entry. The HouseGuest with the most votes automatically returned to the house, while the HouseGuests who finished second and third faced a house vote for a final spot. As Keila was ejected and Andrea left for health reasons, they were both ineligible to take part in the second repechage, and Petrona (who was evicted in Week 9) declined to take part in the second repechage.
The Golden Ticket.
As a result of Luca's ejection on Day 85, it was announced on that same day that the "Golden Ticket" returned. It would give one person (from the previously evicted HouseGuests or contestants from previous seasons) a chance enter the house to replace Luca. On Day 87, it was announced that a second "Golden Ticket" would be given to another former HouseGuest out of the 32 former HouseGuests that chose to participate.
On Day 115, Juliana walked from the game and therefore another "Golden Ticket" was given to a former HouseGuest chosen by "Gran Hermano". One day later, it was announced that Catalina Gorostidi (former season 11 HouseGuest) would return to the house.
HouseGuests.
A total of 24 HouseGuests moved into the house on Day 1 (2 December 2024), making it the season with the highest number of newcomers that join the house in the first episode. Former evicted HouseGuest Brian Alberto returned to the house on Day 35 (5 January 2025), and on Day 36 (6 January 2025) it was announced that new HouseGuest Katia Fenocchio would enter the house as a replacement. Other evicted HouseGuests Jenifer Lauría and Luca Figurelli returned to the house on Day 43 (13 January 2025) and Day 64 (3 February 2025), respectively.
Due to a repechage during Week 10, Renato Rossini, Giuliano Vaschetto and Delfina De Lellis re-entered the house on Days 65 (4 February), 67 (6 February) and 71 (10 February 2025), respectively, while another eight new HouseGuests (Eugenia Ruiz, Gabriela Gianatassio, Lorenzo De Zuani, Lucía Patrone, Marcelo Carro, Saif Al Sayedd, Santiago Larrivey and Selva Pérez) entered the house on Day 71 (10 February 2025). On Day 99 (10 March 2025), Claudio Di Lorenzo (previously walked from the house due to medical reasons) and Juliana Scaglione (former season 11 contestant) received the most votes and re-entered the house via "Golden Ticket".
Relatives.
On Day 141 (22 April 2025), relatives from each one of the twelve remaining HouseGuests that were in competition at the time entered the house.
Episodes.
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Voting history.
HouseGuests nominate for two and one points, shown in descending order in the nomination box. The four or more HouseGuests with the most nomination points face the public vote.
HouseGuests can also use the Diary Room's Special Nomination, which gives three and two points instead. 
From week 2 onwards, the last evicted HouseGuest has the power to void any one's nominations before they nominate in the Nominations Gala.
Starting in Week 23, the Power Nomination (fulminante in Spanish) was enabled by "Gran Hermano", which consists of the automatic nomination of a HouseGuest, without the ability to be saved by the Head of Household. It could only be used once by each HouseGuest throughout those weeks. HouseGuests that use the Power Nomination are marked in bold.
Color key:
Production.
Development.
"Gran Hermano" is co-produced by production companies Kuarzo Entertainment Argentina and Banijay. The season was first confirmed on 3 July 2024. Host Santiago del Moro was also confirmed to return for the season. Casting for the season started on the same day of the announcement with open-call auditions held for people from up 18 years old. Applicants had to upload a presentation video and show their social networks.
Production design.
The house is located in Martínez, Buenos Aires. As with previous seasons, the house is outfitted with 65 cameras and 87 microphones. With over 2,500 square metres, it would become the biggest house ever of "Gran Hermano Argentina", including 1,200 m2 indoors, 400 m2 outdoors, a supermarket, and the "arena" in which the HouseGuests are expected to compete for games and challenges.
Prizes.
The winner of the series, determined by the audience, will receive AR$70 million pesos (invested by Mercado Pago). The runner-up will receive AR$20 million pesos, the second runner-up will receive AR$10 million pesos, and the third runner-up receive a vacation trip for two to Bariloche. All four finalists will receive a motorcycle from Motomel while the HouseGuests who finish in the final three will each win a house from Roca Viviendas, and a year's worth of beer from Amstel.
Release.
Broadcast.
The premiere of the twelfth season of "Gran Hermano" was broadcast on Telefe on 2 December 2024. The telecast received a 17.5 household rating. The most watched episode was the first part of season finale that aired on 24 June 2025 with a 19.8/72 HH rating/share. Throughout its broadcast, in same-day viewership, the season averaged a 12.7 HH rating.
The season airs from Sundays through Thursdays on Telefe, with nomination galas on Wednesdays, eviction galas on Sundays, debates on Mondays, Tuesdays and Thursdays, and a special edition called "Night with the Exes" ("La Noche de los Ex" in Spanish) hosted by Roberto Funes Ugarte, with former HouseGuests from previous seasons on Fridays. The debates are joined by panelists Laura Ubfal, Gastón Trezeguet, Sol Pérez, Eliana Guercio and Ceferino Reato, Costa, Pilar Smith and newcomer Marina Calabró.
Internationally, the season airs in simulcast in Uruguay on Canal 10.
Streaming services.
DirecTV's video streaming service DGO was chosen to offer a 24-hour live feed of the house. Telefe airs in simulcast the season via YouTube and Twitch, hosted by Lucila Villar, Juan Ignacio Castañares and Diego Poggi.