Dual nationals face a specific risk
Iran does not recognise dual nationality. If you hold Iranian citizenship — including by descent, and including if you have never used an Iranian passport — you are treated as Iranian only, and your other government has no consular right to reach you.
British-Iranian, American-Iranian and other dual nationals have been arrested and held for years on charges that were never substantiated. Several governments advise dual nationals not to travel to Iran at all.
No cards, and a guide if you are American or British
Sanctions mean Visa, Mastercard and every foreign bank card are unusable. There are no working ATMs for foreign cards. You must carry the entire cost of your trip in cash — euros or dollars, exchanged locally — with no way to replace it if it is lost or stolen.
Citizens of the United States, the United Kingdom and Canada cannot travel independently: a government-approved guide must accompany them for the whole trip, arranged before a visa is issued.
Dress and conduct
Hijab is legally required for women, including foreign visitors, and enforcement has fluctuated sharply since the 2022 protests. Loose clothing covering arms and legs is expected of everyone.
Photographing government buildings, military sites and airports is prohibited and taken seriously. Alcohol is illegal. Social media posts critical of the state, including ones made before travelling, have led to arrests.