Politicians, the armed forces and veterans were also in attendance at the national memorial service.
As Head of the British Armed Forces, the monarch traditionally lays the first wreath at the Cenotaph and the King looked visibly emotional as he placed the first tribute.
Queen Camilla, Princess Kate and Duchess Sophie, Vice Admiral Sir Tim and the Gloucesters watched the service from the balcony of the Foreign, Commonwealth & Development Office.
The King, Prince William, Princess Anne and Prince Edward were all dressed in military uniform for the service.
Around 10,000 veterans and 800 Armed Forces personnel members from all three services marched past the Cenotaph on Sunday, with thousands more members of the public lining Whitehall in London to pay their respects.
As the bells of Big Ben tolled eleven, and a single gun on Horse Guards Parade was fired, two minutes of complete silence was held in remembrance of all lost in war.
After a further round of gunfire signifying the end of the silence, the bugle call 'The Last Post' was played
The special significance behind the royal family's wreaths
The King's wreath closely resembled the one created for his late grandfather King George VI.
Meanwhile, the Queen's equerry, Major Ollie Plunket of The Rifles, laid a wreath on Her Majesty's behalf, which closely resembled that made for the late Queen Mother. Both wreaths were produced by Camilla's patronage, The Poppy Factory.
Prince William also placed wreath at the Cenotaph, featuring The Prince of Wales plumes and a ribbon in Welsh red.
The royal family's attendance at the Remembrance service comes the day after they watched the performance at the Festival of Remembrance at London's Royal Albert Hall on Saturday night.
The royals wear black as a sign of respect
While the King, the Prince of Wales, the Princess Royal and the Duke of Edinburgh all donned their uniforms, the Queen, the Princess of Wales and the Duchess of Edinburgh wore black as a mark of respect.
Camilla donned a black number by her go-to designer Fiona Clare with a feathered black hat, pearl accessories and a poppy.
Kate looked elegant in a repeat Catherine Walker military-style jacket with a Philip Treacy hat that dates back to her pre-royal days. She also debuted a pair of pearl earrings which belonged to the late Queen Elizabeth II.
Sophie wore a floral printed Suzannah London dress with a boater-style hat, pearl earrings and three poppies pinned to her left lapel.
Why did Princess Kate and Duchess Sophie wear three poppies?
Small red poppies are worn as a mark of respect to those who died during conflict, and the royals wore brooches and pins throughout Remembrance Week.
However, on Remembrance Sunday, the Princess of Wales and the Duchess of Edinburgh noticeably wore three - but what's the significance behind it?
Kate's great-grandmother had three brothers who were killed in action during the First World War and back in 2018, the royal viewed letters from her ancestors during a poignant visit to the Imperial War Museum.
However, the reason for Kate wearing multiple poppies has never been confirmed by the palace.
Another theory is simply because a corsage of poppies is much more visible than one.
The late Queen Elizabeth II used to wear five poppies and it is thought that they represented each service in the war: the Army, the Navy, the RAF, the Civil Defence and women.
LISTEN: How Prince William is helping to save the world