Most foreign nationals need a US B-1 business visitor visa to attend the AAO Conference & Expo; nationals of Visa Waiver Program countries can instead travel under an approved ESTA. Permitted B-1 activities expressly include attending a scientific, educational, professional or business convention or conference and negotiating contracts.
Estimated cost: USD 185 standard US nonimmigrant visa (MRV) application fee, non-refundable and non-transferable; USD 21 for an ESTA authorisation under the Visa Waiver Program.
Processing: B-1 interview appointment waits vary by consulate and can range from a few weeks to several months, so apply 3-6 months before travel. ESTA authorisations for Visa Waiver Program travellers are typically issued within 72 hours, though additional review can take longer.
Schedule the visa interview at the US embassy or consulate in your country of residence or nationality and bring your AAO registration confirmation plus an invitation letter. Attending a scientific, educational, professional or business convention is an explicitly permitted B-1 activity. Apply early because October is a busy meeting month in New Orleans and appointment slots fill quickly.
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