ETIAS is the EU's new travel authorisation system. It is scheduled for introduction towards the end of 2026. It is a similar concept to the USA's ESTA and the UK's ETA scheme. After launch, travellers will need to apply ahead of departure for it.
When up and running, if you are not a citizen of the EU or a Schengen Area country, and are travelling to the EU for a short stay, then you will need an ETIAS. A short stay refers to visits, holidays or business trips up to 90 days within any 180 day period.
An ETIAS will likely cost 20 Euros. It will last for three years and during this time you will be able to travel on multiple trips using the same ETIAS. However, if your passport expires during the ETIAS validity period, you will need to apply for a new ETIAS.
Applications will need to be made through the official website https://travel-europe.europa.eu/etias. Do not use an unofficial website and be aware that there are fake websites offering ETIAS. Note that until ETIAS is operational, applications will not be live via the website.
You will need to do one application for each traveller. Each application will require you to provide personal information including name(s), date and place of birth, sex, nationality, home address, email address and phone number, passport/travel information, level of education and current occupation, details about your intended travel and stay, details about any past criminal convictions, past travels to war or conflict zones and whether you have recently been the subject of an extradition. Details must match your passport otherwise the ETIAS will not be valid.