There is no requirement for Irish and British citizens to carry passports when travelling within the Common Travel Area. However, many air and sea carriers require some form of identification and some carriers regard a passport as the only valid identification.

For Irish and British citizens, flying domestically within the Republic of Ireland (such as from Dublin to Kerry) technically does not require a passport under Irish law, as there are no immigration controls. However, the airline's specific "Terms and Conditions" are the deciding factor. As of early 2026, Aer Lingus (which typically operates this route via Aer Lingus Regional) has implemented stricter identification policies. While they previously accepted various forms of photo ID, they now increasingly require a valid Passport or an Irish Passport Card for all flights to ensure consistency across their operations. Other airlines or regional carriers might still accept a valid government-issued photo ID, such as a National Driving Licence or a Public Services Card, but it is risky to travel without a passport. If you are a non-EU/EEA citizen, you are legally required to carry your passport at all times when traveling, even on domestic flights. To avoid being denied boarding at Dublin Airport, the safest and most reliable form of identification to bring is your passport or Passport Card, regardless of your nationality.