Question: Can you get a visa on arrival at the airport? Or can you get a visa on arrival if you have LOI? I am a South African citizen.
Answer: VOA is issued for 98 nationalities excluding USA, England, Canada, Colombia, Pakistan, Afghanistan, Iraq, Jordan, Bangladesh, and Somalia. If your nationality is among the countries authorized to get it, you can collect your visa against offering your passport, a passport-size photo and about $50 to the staff at the airport. There is no need to fill in any form beforehand.
You can also fill in the visa form on http://www.uppersia.com/Iran-travel-services/iran-visa.html, it takes about 10 working days to get your reference number and two working days to collect your visa at the embassy by direct referral or one working week by posting the docs to the embassy. You can pay the visa fee in cash in Iran.
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