Different rules apply to a king: King Charles not only inherited the throne from the Queen, but also a special freedom to travel. Charles does not need a British passport when traveling abroad. This can be read on the official website of the British royal family.
King Charles jets around the world without a passport
Instead of a passport, the king is issued a document with a royal coat of arms on it. “The Secretary of State to Her British Majesty, on Her Majesty’s behalf, requests and urges all those concerned to allow the holder of the passport free passage without obstruction and to give him such assistance and protection as may be necessary.” , it says.By the way, all other members of the royal family have passports.
The Japanese imperial couple can also do without a passport
Two other people are traveling around the world in a relaxed manner without a passport: the Japanese Emperor Naruhito and his wife, Empress Masako. This is reported by the “Asia Mirror” and refers to a government document. A ministry document was drafted in 1971, according to which it was “highly inappropriate” to issue a passport to the Emperor or Empress. It was “highly inappropriate” for the couple to submit to an immigration or visa process with a passport like a normal citizen.
However, the imperial couple of Japan must present the document in each country they enter. The Japanese Ministry of Foreign Affairs must also inform the destination country in good time about their trip. The remaining family members travel on diplomatic passports.
Source: https://www.focus.de/kultur/royals/nur-drei-menschen-auf-der-welt-brauchen-keinen-reisepass_id_200844152.html
