Many of the plans for the service, code named Operation Golden Orb, are being kept under wraps.
But Buckingham Palace has revealed some details about the celebrations planned to mark the event.
The coronation will be conducted by the Archbishop of Canterbury.
According to the palace it will be “a solemn religious service, as well as an occasion for celebration and pageantry”.
It will “reflect the monarch's role today and look towards the future, while being rooted in longstanding traditions”, the palace said.
He will later wear the Imperial State Crown, which contains the Cullinan II diamond.
The queen consort will wear a modified version of Queen Mary’s crown during the service, the first time a crown will be reused for a coronation instead of a new one being commissioning.
It will not feature the Koh-i-noor diamond, a famous but controversial gem that been part of the British crown jewels since being seized from India in the 19th century.
In tribute to Queen Elizabeth II, the crown will instead be reset with the Cullinan III, IV and V diamonds.
After the ceremony, which will involve several stages, including pledging an oath to uphold the law and the Church of England, the couple will return to Buckingham Palace, where they will appear on the balcony with other members of the royal family.
The guest list
Royals from both home and abroad will attend the event.
The guest list is expected to include the entire British royal family, including Princess Anne, Prince Andrew, Prince Edward, along with his son, Prince William, and daughter-in-law Catherine, Princess of Wales.
Monaco’s Prince Albert and Princess Charlene have also confirmed they will attend.
The UK Prime Minister will also attend the coronation, as will other heads of state, and representatives from the British Houses of Parliament.
An official government playlist has been compiled to celebrate the coronation.
Hits on the playlist, which runs for one hour and 56 minutes, include The Beatles' Come Together, Boney M's Daddy Cool, Treat People With Kindness by Harry Styles, Kate Bush's Running Up That Hill, the Spice Girls' Say You'll Be There and the appropriately titled King by Years & Years.
A track by grime artist Dizzee Rascal was removed because of his domestic violence conviction.
The queen consort has been a campaigner against domestic violence for years.
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There will also be notable citizens from Commonwealth countries.
Westminster Abbey has a maximum capacity of about 2,200.
The Harry and Meghan question
Relations between the couple and the rest of the royal family became strained after the release of their Netflix documentary and Prince Harry’s book.
In an interview to promote his autobiography, the prince said: “There's a lot that can happen between now and then. But, you know, the door is always open.
“The ball is in their court. There's a lot to be discussed, and I really hope that they are willing to sit down and talk about it.”
The palace reportedly plans to invite Prince Harry and his wife Meghan, but the invite is apparently yet to be extended.
The coronation weekend will feature a star-studded concert, nationwide “big lunch” and volunteering initiative, as well as the traditional ceremony and royal processions.
The three days of ceremonial, celebratory and community events in early May will be a chance for “people to come together in celebration of the historic occasion”, Buckingham Palace announced recently.
The palace is asking neighbourhoods around the nation to take part in the “Coronation Big Lunch’’ on Sunday, May 7 — the latest incarnation of the block parties that have become a staple of big royal celebrations.
That night there will be a star-studded concert at Windsor Castle featuring a choir drawn from amateur troupes across the United Kingdom, including refugee choirs, National Health Service choirs, LGBTQ singing groups and deaf signing choirs.
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During the concert, locations across the country will be lit up using projections, lasers and drone displays.
Some 10,000 free tickets are up for grabs to the event, with members of the public invited to apply by visiting www.bbc.co.uk/coronationconcert. The ballot closes just before midnight on February 28.
The next day, the palace is inviting people around the country to take part in ‘’The Big Help Out”, encouraging them to volunteer in their own communities and pageantry”.
There will be a Bank Holiday on Monday, May 8, to celebrate.
How to watch
The ceremony, like the concert the following day, will be screened worldwide. Hundreds of millions of people are expected to tune in to watch the coronation.
But for anyone who wants to see the action first-hand, the prices of London hotels for the weekend have already rocketed.
According to accommodation search website Trivago, London hotels have ramped up their prices by 60 per cent year on year for the coronation, with prices hitting £254 a night for early bookers.
But as hotels increase their prices to capitalise on the expected surge in visitors, booking trends suggest that many visitors may be shunning London on the day of the ceremony.
Trivago data shows that the search share for the capital for the day of the coronation is lower than for the weekend before and the one after the ceremony, while searches for London are also down 8 per cent compared with the same day last year.