Presidents, prime ministers and royals from across the globe came together as guests of the monarch for the event on Sunday evening.
The couple arrived in the presidential car known as The Beast in the middle of a convoy of vehicles at the back of the palace shortly before 6pm.
Members of the president’s entourage mingled with household staff and police next to the palace lawn while the reception took place inside.
Around 200-250 leaders were invited, with most bringing their spouse, including France’s President Emmanuel Macron who was joined by his wife, first lady Brigitte.
The Prince and Princess of Wales and other working members of the royal family including the Earl and Countess of Wessex, the Princess Royal and Vice Admiral Sir Tim Laurence, and the Duke and Duchess of Gloucester joined Charles and the Queen Consort in mingling with guests.
Dozens of leaders of Commonwealth countries and members of foreign royal families also attended the reception.
At least 10 coaches arrived filled with guests, who solemnly walked into the palace.
Some leaders were seen greeting each other while others remained silent as they walked up the steps.
Most of the guests were all dressed in black, while some were seen wearing traditional clothing native to their countries.
European Commission president Ursula von der Leyen and president of the European Council Charles Michel arrived on coaches with several leaders of Commonwealth nations at the Grand Entrance.
They were joined by New Zealand Prime Minister Jacinda Ardern, who walked into the palace followed by Canadian Prime Minister Justin Trudeau, who smiled briefly at journalists.
Brazilian President Jair Bolsonaro was also among guests at the event which took place across the picture gallery, the white drawing room, the blue drawing room and the music room.
Guests arriving in their own vehicles and going through the Bow Room entrance at the back of the palace included the Bidens, Prime Minister Liz Truss, Foreign Secretary James Cleverly, and President of Israel Isaac Herzog.
President of Ireland Michael D Higgins arrived on a coach with the former King and Queen Consort of Spain, Juan Carlos and Sofia.
The trio joined dozens of other dignitaries who went in the Grand Entrance at the front of the palace.
King Abdullah II and Queen Rania of Jordan arrived in their own vehicle at the Grand Entrance and were followed by their son, Hussein, Crown Prince of Jordan, who also took his own vehicle.
Moments later, the Emir of Qatar, Tamim bin Hamad Al Thani, arrived.
King Hamad bin Isa Al Khalifa and the Crown Prince of Bahrain, Salman bin Hamad Al Khalifa, also joined the guests, and the Crown Prince of Kuwait, Nawaf Al-Ahmad Al-Jaber Al-Sabah, soon followed.
The Sultan of Oman was also seen arriving at the palace, while Ruler of Dubai Mohammed bin Rashid Al Maktoum followed shortly afterwards.
King Felipe and Queen Letizia of Spain, King Carl XVI Gustaf and Queen Silvia of Sweden, and Queen Margrethe II of Denmark were among those arriving on coaches.