Visa-exempt visitors (EU/EEA, US, Canada, Australia, Japan, South Korea, Singapore and Gulf nationals, among others) need a UK Electronic Travel Authorisation (ETA, £16, valid 2 years, up to 6 months per visit) before travelling; British and Irish citizens need no permission. Nationals of visa countries such as India, China, Nigeria and Pakistan require a Standard Visitor Visa (£127, typically around three weeks to process). Business meetings, networking and attending a trade fair are permitted on a standard visit — verify permitted activities on GOV.UK before booking.
Estimated cost: Varies by visa type and nationality (check official site).
Processing: Varies by nationality; apply several weeks before travel.
Applied for online via GOV.UK; no biometrics appointment. Attending a trade fair as a business visitor is allowed on a standard visit. Covers business meetings, networking and attending trade fairs; selling goods or paid work on a stand may need a different permission — check the GOV.UK 'permitted activities' list.
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