Travelers planning a visit to the United Kingdom should understand the Electronic Travel Authorisation (ETA) rules before departure. Eligibility depends on nationality, passport type, and the purpose of travel. To check passport eligibility UK ETA, applicants should confirm that their nationality is included in the eligible country list and that their passport meets the required conditions. A valid biometric passport, personal details, and a recent photograph may be needed during the application. Checking eligibility in advance helps travelers avoid delays, prepare the correct documents, and ensure they have the necessary travel permission before boarding their flight.