To enter the United States of America, a passport valid for the duration of stay is required by nationals in the chart above. Passport note : All travellers entering the USA under the Visa Waiver Program require individual machine-readable passports.he length of stay in the USA is determined by US immigration officials at the time of entry. Transit : Travellers who are visa-free under the Visa Waiver Program do not require a transit visa, but must obtain ESTA-authorisation prior to travel.