How does the Catholic Church choose a new pope?

How a new pope is chosen

Whenever a pope dies—like Pope Francis in April 2025—or whenever a pope steps down, as Pope Benedict XVI did in 2013, a new leader must be chosen. The new pope becomes the Church’s administrative leader and he provides spiritual guidance to 1.4 billion Catholics around the world.

And the duty to choose falls on the College of Cardinals.

The College of Cardinals is a body of senior Catholic clergy who advise the pope and, in the event of a vacancy, elect his successor. Cardinals serve as the pope’s closest advisors on matters of faith, doctrine, Church governance, and global issues. They represent the Church at international events and they meet with world leaders. There’s no fixed number of cardinals; this year, 2025, there are 252 of them, from many different countries. Each cardinal is appointed by a pope and serves for life.

And then, about every ten to fifteen years, the College of Cardinals must perform its most solemn duty: election of a new pope.

Not all cardinals can vote on a new pope. To participate in the election of a new pope, a cardinal must be under the age of 80 when the vacancy happens. The cardinals who are eligible are called the cardinal electors. Vatican policy says there should be just 120 of them, but the Conclave of 2025 will have a few more.

When a pope dies, the Church observes an official mourning period of at least nine days. Then, all the cardinals travel to the Vatican for a meeting called “General Congregations.” In the General Congregations, the cardinals set the stage for the coming papal election. They discuss the state of the Church, the challenges ahead, and the qualities needed in the next pope. In these meetings, the cardinals get to know each other better, and they start to form thoughts about who would make a good leader.

The election process is called the Conclave. On day one of the Conclave, the cardinal electors celebrate a special mass at St. Peter’s Basilica in Vatican City. It’s called the Mass for the Election of the Roman Pontiff, and its purpose is to ask for guidance in choosing the next pope. It sets a prayerful and solemn tone for what’s to come.

In the Conclave, all cardinal-electors—the cardinals under the age of 80—proceed to the Sistine Chapel in Vatican City. “Conclave” means “with key” in Latin, and during the Conclave, the cardinals are locked inside the chapel to ensure secrecy. They have no contact with the outside world, and the outside world has no contact with them. Only a small number of support staff have access to the cardinals during the Conclave—cooks and doctors, for example.

Once inside, the cardinals vote. And they begin voting relatively quickly. The first ballot is often taken the same day that the Conclave begins.

So how do the cardinals know who to vote for? Any baptized male is eligible to be pope, but for the last 600 years, the cardinals have chosen one of their own. They make their first choice based on their knowledge of each other and from what they learned during the General Congregations.

Remember, the General Congregations are the pre-meetings, in which cardinals speak about the state of the Church and the challenges it faces in the future. This is where individual cardinals can make their views known. And the cardinal electors begin to think about who would make a suitable leader.

Inside the Conclave, though, there are no nominations and there are no speeches. There’s no campaigning for the job. Cardinals vote in silence and in prayer. Every cardinal writes one name on a piece of paper. They place their secret ballots into a silver urn and proclaim “before God” that they have voted their conscience. When all votes have been submitted, the results are read out inside the chapel, and the cardinals know who received votes, and how many.

To become pope, a cardinal needs a two-thirds majority of the votes. Most often, no cardinal receives a two-thirds majority on the first ballot.

After the first ballot is complete, and after the results have been read out, the ballot papers are burned in a special stove in the chapel. If no cardinal has received two-thirds of the votes, a special chemical is added to the fire to turn the smoke black.

Outside, cameras trained on the Sistine Chapel capture a plume of black smoke, and Catholics around the world know no pope was elected in the first round.

The process repeats, with up to four ballots per day, two in the mornings and two in the afternoons, until someone reaches the required number of votes. In between the ballots, cardinals may have private conversations. Cardinals who have received votes may choose to step aside, to encourage their colleagues not to vote for them. But explicit campaigning is prohibited.

Each time a ballot concludes, the ballot papers are burned. And each time no cardinal receives a two-thirds majority, the smoke is black.

When a cardinal finally does reach that two-thirds majority, the Dean of the College of Cardinals asks him, in Latin, “Do you accept your canonical election as Supreme Pontiff?” If he responds “I accept,” then he is the pope. The Dean then asks, again in Latin, “By what name shall you be called?”

The new pope chooses his papal name at that moment. The final ballots are then burned—and this time the smoke is white. The bells of St. Peter’s Basilica ring. And the world knows a new pope has been elected.

The new pope is taken into a special room in the chapel to change into his papal vestments, the ceremonial clothing of a pope. The Cardinal Protodeacon—a senior official—goes to the balcony of St. Peter’s Basilica and announces, “We have a pope!” He announces the birth name, and the chosen papal name, of the Church’s new leader.

Minutes later, the new pope greets the faithful gathered outside. He gives his first blessing as pope, called “to the city and the world.”

Jeff’s take

There’s a saying in Italian, “he who enters the Conclave a pope, comes out a cardinal.” “He who enters the Conclave a pope, comes out a cardinal.”

That means the front-runner—the one who seems most likely to win at first—rarely ends up as pope. That’s what multiple ballots can do; it’s common for someone to build momentum and build support throughout the Conclave. But of course we can’t study in detail, since the ballot papers are secret, and the cardinals are sworn to secrecy.

In the Middle Ages, the election of a new pope could take weeks or even months. Different factions battled one another for supremacy. More recently, it has taken just a few days. One modern pope was elected on the first ballot. That was Pope Pius XII in 1939. This was the eve of World War II; storm clouds were gathering in Europe, and the cardinals may have wanted to choose a new leader decisively.

The more typical situation is that a new pope is chosen within a few days. Pope Francis was elected on the fifth ballot; Pope Benedit XVI on the fourth; Pope John Paul II on the eighth ballot.