Key workers, charity volunteers and members of the armed forces will celebrate the Queen's 70 years on the throne at a thanksgiving service - although the monarch will not be there herself.
More than 400 people, who have been making a difference either nationally or locally, will be among the guests at St Paul's Cathedral tomorrow.
They will join members of the royal family, but those hoping to get a view of the Queen will be disappointed, as she pulled out having experienced "some discomfort" during Thursday's events.
Senior members of the monarchy attending include the Prince of Wales, Duchess of Cornwall, the Duke and Duchess of Cambridge and the Duke and Duchess of Sussex, who will be joined by the extended royal family.
Charles will officially represent the Queen at the service.
The Duke of York was expected to attend but has now withdrawn after testing positive for Covid.
The Dean of St Paul's, Dr David Ison, will say in The Bidding: "We come together in this Cathedral Church today to offer to God our thanks and praise for the reign of Her Majesty the Queen and especially for her 70 years of faithful and dedicated service.
"As we gather from communities across her realm and the Commonwealth of Nations, we rejoice in the diverse and varied lives of all those whom she serves, and in the beauty and abundance of the world in which we live.
"Inspired by words and music, we pray that God will continue to bless and guide Her Majesty, and that we may all receive grace to honour life and to live in harmony with one another; and we continue to pray for those whose lives are marred by conflict, suffering and tragedy.
"And mindful of the call of God to look to the needs of others, we commit ourselves afresh to caring for our world and all for whom it is home, striving always to seek out and nurture that which is good in people and in all creation."
Those invited in recognition of their service have all been recipients of honours in the New Year or Birthday Honours lists and their number also includes public servants and representatives from social enterprises and voluntary groups.
Boris Johnson, who will give a New Testament reading, and members of his Cabinet are among the guests along with Labour leader Sir Keir Starmer, first ministers of the devolved governments and former prime ministers.
The diplomatic world will be represented by high commissioners and ambassadors from across the world and also attending are governors general and clergy from world faiths.
The Archbishop of York Stephen Cottrell will give the sermon after the Archbishop of Canterbury Justin Welby tested positive for Covid-19. The Dean of the Chapel Royal, Dame Sarah Mullally, Bishop of London, will give the Collect and the Blessing, and the Dean of St Paul's will conduct the service.
Young people representing countries where the Queen is head of state will lead the 'Act of Commitment' celebrating the life and reign of the monarch, led by the Reverend Robert Kozak.
During the day, one of the country's largest bells, the Great Paul, will be rung before and after the service, the first time it will have been heard at a royal occasion.
The event will feature a new anthem by Judith Weir, Master of the Queen's Music, that sets to music words from the third Chapter of the Book of Proverbs.
Bible readings, hymns and prayers to express thankfulness for the Queen's reign, faith and service will also be heard by the congregation as the nation marks the monarch's 70 years on the throne.
Before the service begins, the Band of Her Majesty's Royal Marines Portsmouth (Royal Band), will play as the congregation arrives and the State Trumpeters of the Household Cavalry will perform to mark royal arrivals, while the Fanfare Trumpeters of the Central Band of the Royal Air Force will accompany later in the service.
The choirs of St Paul's Cathedral and Her Majesty's Chapel Royal will join together to sing the Vivats, I Was Glad by Sir Hubert Parry, performed at every coronation and now for the Queen's Platinum Jubilee.
