Three days was tight for anyone juggling a long-haul packing list; seven days is workable. Taiwan has widened the submission window for its compulsory digital arrival card (TWAC), which every foreign visitor arriving by air or sea has needed since October 2025 — British passport holders included, even though the entry itself is visa-free.
Filing happens on the official portal (English among seven languages), starts with an e-mail verification, and covers passport data, purpose of visit, flight or ferry details and your accommodation. Households travelling together can go in one combined submission, and the card remains editable up to the document check at immigration — keep the confirmation e-mail, as its document number unlocks any later corrections.