Soon after 7pm on Friday the Vatican ended a TV broadcast of the visits that had been running nearly continuously, ahead of a private ceremony to seal his casket.
As Italian and Vatican police prepared to close the long queue through the central nave of the church, the last visitors shuffled in.
The 88-year-old pope, who had led the Church since 2013, died on Monday in his rooms at the Vatican's Santa Marta guesthouse after suffering a stroke as he was recuperating from weeks of pneumonia.
About 250,000 people from all over the world have lined up to say farewell since his body was brought to St. Peter's on Wednesday to lie in state, the Vatican said.
Among the last visitors were French President Emmanuel Macron and his wife Brigitte, who stood together at the side of the casket for a few moments. He bowed his head; she made the sign of the cross.
Long queues snaked around St. Peter's Square and the surrounding roads all day on Friday. Some waited hours for the chance to spend a few minutes inside the basilica and pay their respects.
A conclave to choose a new pontiff is unlikely to start before May 6. In the meantime, the world's Catholic cardinals have assumed temporary control of the 1.4-billion-member Roman Catholic Church.
Cardinals present in Rome are convening almost daily, primarily to discuss logistical matters, in what is called a "general congregation".
A total of 149 of the world's 252 cardinals were present for the meeting on Friday morning, the Vatican said, with dozens more expected to arrive through the rest of the day.
The private ceremony to seal Francis' coffin will be led by eight Catholic cardinals, including a US prelate who has faced criticism over his handling of sexual abuse cases. Among those also present will be the late pope's secretaries.
The Vatican on Friday said it is expecting 160 foreign delegations to attend Saturday's funeral, among them dozens of world leaders including US President Donald Trump and 10 reigning monarchs.
There had been speculation that foreign leaders might have diplomatic meetings on the sidelines of the funeral to discuss the war in Ukraine, but the Elysee Palace said on Friday that Macron would not host any such meetings.
Trump was due to spend only about 15 hours in Rome, arriving late on Friday evening and leaving directly after the funeral.
Authorities began ramping up security ahead of the ceremony, with snipers on rooftops, drones watching from the sky and an army device readied to neutralise hostile flying objects.
The heart of Rome is expected to be closed to traffic on Saturday to allow a funeral motorcade carrying the pope's remains to make its way slowly to the Basilica of Santa Maria Maggiore (St. Mary Major), where Francis, in a break from tradition, asked to be buried instead of St. Peter's Basilica.
Crowds are expected along the route, which will pass by many of Rome's famed monuments, including the Colosseum.
The pope's tomb will be in a niche in a side aisle of the basilica, with just the word "Franciscus", his name in Latin, engraved on the marble.
16°C