Lieutenant Governor Sir John Lorimer, officially a member of the royal household, is expected to attend.
The service will take place at Westminster Abbey in London.
The historic church is where Britain’s kings and queens are crowned, and where Queen Elizabeth II married Prince Philip in 1947.
Heads of state from across the world will be invited to join members of the Royal Family to remember the Queen.
Senior UK politicians and former prime ministers are also expected to attend the service, which will be televised.
The service will likely be conducted by the Dean of Westminster David Hoyle, with the Archbishop of Canterbury Justin Welby giving the sermon.
The UK’s prime minister Liz Truss may be called on to read a lesson.
The day will be a bank holiday in the UK. The Isle of Man is likely to follow suit.