According to the official site of the British Monarchy, the Queen does
not have or need a passport:
QUEEN AND PASSPORT
"When travelling overseas, The Queen does not require a British
passport. The cover of a British passport features the Royal Arms, and
the first page contains another representation of the Arms, together
with the following wording:
'Her Britannic Majesty's Secretary of State requests and requires in
the name of Her Majesty all those whom it may concern to allow the
bearer to pass freely without let or hindrance and to afford the
bearer such assistance and protection as may be necessary.'
As a British passport is issued in the name of Her Majesty, it is
unnecessary for The Queen to possess one. All other members of the
Royal Family, including The Duke of Edinburgh and The Prince of Wales,
"...The Queen does not own a passport, despite making numerous
official visits overseas. As you point out, because the British
passport is issued in the name of the Sovereign, it is not necessary
for The Queen herself to have one."
"queen * a passport"
site:.royal.gov.uk queen passport
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