For the first time since 1973 the Queen will not be attending the Commonwealth heads of government meeting this year, Buckingham Palace has said.
She will be represented by the Prince of Wales at the summit in Sri Lanka in November.
Buckingham Palace said it was reviewing the amount of long-haul travel the Queen undertook.
The Queen, 87, is the head of the Commonwealth and every two years leaders meet to discuss global issues.
The Queen was first present at the Commonwealth heads of government meeting (Chogm) in Ottawa, Canada, in 1973 – missing the first one in 1971 – and has been at every summit since. The last one, in 2011, was held in Perth, Australia.