The ceremony is an annual Sunday service that is closest to November 11, the day the 1918 World War ended.
A two-minute silence was also observed to remember the dead when Big Ben struck at 11am.
British Prime Minister Boris Johnson and Labor Opposition Leader Jeremy Corbyn also attended the ceremony and wreathed wreaths during the election campaign.
The Royals also paid tribute on Saturday night at the Royal British Legion Festival of Remembrance at the Royal Albert Hall.
The memorial service, hosted by the Royal British Legion, was the 75th anniversary of the key battles of 1944, including Monte Cassino, Kohima, Imphal and D-Day, highlighting in particular the role of the Commonwealth and the Allied Forces.
It also celebrated the 100th anniversary of the Government Communications Headquarters (GCHQ) and honored the company of RFA Mounts Bay, which contributed significantly to the transportation of supplies and relief supplies to the Bahamas following Hurricane Dorian in September.
During the week, events took place in honor of all victims of conflict. On Thursday, Meghan visited the field of memory at Westminster Abbey for the first time with her husband. The royal couple placed small crosses there to honor the dead of the war.
Duchess Camilla – the wife of Prince Charles – took part in the engagement after a Clarence House spokeswoman announced that she was leaving the event due to a breast infection.
Earlier this week, the Queen paid a visit to the Royal British Legion Industries village in Aylesford, south east England, which provides housing and social assistance for veterans and the wider community of armed forces.