Flying without a physical ID in the UK is technically possible for some domestic flights, but it is highly discouraged as policies vary significantly between airlines. Most carriers, including British Airways and easyJet, allow photographic ID such as a driving license, citizen card, or an expired passport (if it's within a certain timeframe, usually up to 2 years after expiry). However, for domestic travel between England, Scotland, and Wales, some airlines used to allow travel without a photo ID if you had no checked baggage, but in 2026, security protocols have tightened. Starting in late February 2026, the UK government began enforcing the Electronic Travel Authorisation (ETA) for non-visa nationals, and while this primarily affects international visitors, it has pushed the overall system toward more stringent digital and physical document checks. For British citizens, a valid passport remains the most reliable document. If you lose your ID, you must contact your airline immediately; some may accept a combination of non-photo documents like birth certificates or utility bills alongside a police report, but you will likely face intense additional security screening and could still be denied boarding.