Most international attendees travelling to the United States for a business event need either a B-1 business visitor visa or travel under the Visa Waiver Program if their country is eligible. Confirm your exact category on the U.S. Department of State business visa pages before booking.
Processing: Varies by nationality; apply several weeks before travel.
The U.S. Department of State business visa page and the USCIS B-1 Temporary Business Visitor page both describe B-1 as the category for attending conferences, meetings and consultations. Visa Waiver Program travellers must obtain an approved ESTA before boarding. Processing times and fees vary by consulate; check the official pages rather than relying on third-party estimates.
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