The beginning of the conclave, in 7 detailed steps

Here is how the conclave will get underway on May 7, 2025.

In recent days, all the usual occupants of the two houses of Santa Marta – the old structure and the new one – have had to leave the premises. Both buildings have been restructured and secured to accommodate the 133 cardinals who will vote for the election of Pope Francis' Successor. They started moving into the rooms of this Vatican residence on Tuesday morning and will continue until Wednesday, before the Pro Eligendo Romano Pontifice Mass.

Only suite 201 — the apartment of the deceased pontiff — remains unoccupied. It will remain sealed until the election of the new pope, who may take up residence there in the first days of his pontificate. He will also visit the papal apartments in the Apostolic Palace, which were also sealed after Francis' death on April 21, and may choose to move there.

Inaugurated by John Paul II in 1996, the Santa Marta residence was originally designed especially for a conclave. The cardinals who participated in the two conclaves of 1978 — including Joseph Ratzinger, the future Benedict XVI — were housed on camp beds in the corridors of the Apostolic Palace, in very spartan and difficult conditions in the Roman summer heat. With an investment of $20 million, John Paul II therefore decided to support the construction of a new, more modern and secure building for the conclave dedicated to electing his successor.

This 129-room building is usually used as a guest house, but some priests working in the Roman Curia live there full-time -- except during conclaves.

To everyone's surprise, after his election in 2013, Pope Francis chose to reside there permanently, taking possession of the suite occupied by Patriarch Bartholomew of Constantinople, who had come to the Vatican for his installation Mass.

At 10 a.m., all the cardinals — whether electors or not — will celebrate the Pro Eligendo Romano Pontifice (“For the Election of the Roman Pontiff”) Mass in St. Peter's Basilica. Bishops, priests, deacons, religious, and lay faithful may also participate in the celebration, thus manifesting the communion in prayer of the whole Church at such an important moment. This is specified in the Ordo rituum conclavis.

Broadcast by Vatican media, the Mass will be presided over by the dean of the Sacred College, Cardinal Giovanni Battista Re.

At 91, this Italian has presided over the general congregations -- the closed-door meetings during which the cardinals took stock of Francis' pontificate and outlined prospects for the future. The former prefect of the Congregation for Bishops also presided over Pope Francis' funeral Mass; but he will not be able to participate in the conclave as he is over 80 years old.

In his homily, he’s expected to reflect on the Gospel chosen for this Mass, from the Gospel of John recounting Christ's request to his disciples: “This is my commandment: Love one another as I have loved you.” In this passage, which the cardinals will hear, Jesus Christ also says, “You did not choose me, but I chose you and appointed you to go and bear fruit, fruit that will last.”

In March 2013, Cardinal Re's predecessor, Cardinal Angelo Sodano, emphasized in his homily the role of popes in “the service of charity.”

During the prayer intentions for this special Mass, the assembly will be invited to pray for the cardinals “called to elect the Roman Pontiff.” The Mass will conclude with a Latin prayer to the Virgin Mary, the Regina Cæli.

The 133 cardinal electors will then reconvene at 4:15 p.m. in the Pauline Chapel of the Apostolic Palace in the Vatican for a short prayer introducing the procession to the Sistine Chapel. In this Pauline Chapel, which is not usually open to visitors, two frescoes by Michelangelo illustrate the Martyrdom of St. Peter and the Conversion of St. Paul, the two patron saints of the city. The cardinals will be able to gaze into the mysterious eyes of Saint Peter, crucified upside down, who seems to warn the viewer observing him.

The Pauline Chapel, renovated in 2009, is separated from the Sistine Chapel by the splendid Sala Regia, the hall of honor of the Apostolic Palace.

The procession leaving the chapel will be composed of acolytes carrying a cross and two candlesticks. Behind them will come cantors and prelates, including the secretary of the college of cardinals, the master of papal liturgical celebrations, and Cardinal Raniero Cantalamessa, who was chosen to give the meditation.

The cardinals will then follow, divided according to the three orders that make up the College of Cardinals: first the deacons, then the priests, and finally the bishops. All will sing the long litany of the saints in Latin.

After taking their places in the Sistine Chapel, the cardinals will sing the Veni Creator, the Christian prayer asking the Holy Spirit to come and support them.

Then, in the presence of those who took part in the solemn procession, they will take the prescribed oath. The cardinal presiding over the conclave — Cardinal Pietro Parolin — will then pronounce the following formula:

Then, each cardinal elector, according to the order of precedence, shall take the oath in Latin in the following form: “And I, N., Cardinal N., promise, vow, and swear,” and he shall add, placing his hand on the Gospel presented by the ceremonial ministers, “with the help of God and these holy Gospels which I touch with my hand.”

When the last cardinal has taken the oath, the master of pontifical liturgical celebrations, Archbishop Diego Ravelli, will then pronounce the famous formula “extra omnes” – “Everyone out” – telling those not participating in the conclave to leave the Sistine Chapel. The Italian prelate will then close the heavy wooden door separating the chapel from the Sala Regia.

Then, before the cardinal electors, the person chosen to preach a “meditation on the heavy task that awaits them” will speak, according to the Ordo rituum conclavis. Cardinal Raniero Cantalamessa, a non-voting cardinal and longtime preacher of the Papal Household, will fulfill this mission.

The Capuchin friar retired last fall at the age of 90, after an exceptionally long period of active service in the Vatican. He held the position of preacher for 44 years and was one of the last figures from the pontificate of John Paul II still in office.

At the end of this meditation, the preacher and the master of papal ceremonies will leave the premises. The Swiss Guard will be stationed at all entrances to the chapel and the first vote will take place.

The first vote will take place after Cardinal Cantalamessa's meditation, and will then be followed by the first smoke from the chimney. It’s not impossible that a new pope will be elected on the first ballot, but it’s highly unlikely. For this to happen, at least 89 cardinals — out of 133 — would have to vote for the same cardinal. Usually, the first vote serves to gauge the forces at play without prejudging the final result.

After this first vote on Wednesday evening, the cardinals will return by bus to Casa Santa Marta for dinner and to rest for the night. They will be able to talk among themselves but will have no communication with the outside world. They won’t get their cell phones back until after the conclave is over.