If you are a British citizen abroad and have lost your passport or it has expired, you can apply for an Emergency Travel Document (ETD), which functions as a temporary passport for a specific journey. As of 2026, the UK has strictly enforced digital "permission to travel" requirements, meaning that having the correct documentation is more critical than ever. To get an ETD, you must have previously held a UK passport issued after 2006. The process is done online via GOV.UK and usually costs about £100. If you are a non-British citizen looking for a "temporary" entry document, the UK has fully rolled out the Electronic Travel Authorisation (ETA); this is a mandatory digital permit for most "visa-free" national visitors (like those from the US, EU, or Gulf states) and must be obtained before you board your flight. For dual-national British citizens, be aware that you can no longer use a non-UK passport to enter; you must have your valid British passport or an ETD to prove your right of abode. Essentially, "temporary" travel is possible, but in 2026, it is entirely digital and requires pre-approval before you reach the airport.