Passports and Identification. Ireland / Britain routes: Irish Ferries recommends all passengers bring a passport with them. Irish and British citizens do not strictly require a passport to travel between the two countries, but some form of (photo) identification is however required.

As of February 25, 2026, there have been significant updates to travel document requirements for routes between Ireland and the UK. While the Common Travel Area (CTA) still exists—meaning Irish and British citizens do not need a visa to travel between the two countries—airlines and ferry operators have become much stricter. In 2026, major carriers like Aer Lingus and Ryanair now require a valid passport or Irish Passport Card for all passengers. For ferry travel (such as Dublin to Holyhead), while some operators may still technically accept a government-issued photo ID for CTA citizens, the introduction of the UK Electronic Travel Authorisation (ETA) for non-CTA nationals has led to more frequent "full" passport checks at the terminal to verify a passenger's status. Travelers are strongly advised to carry a passport in 2026 to avoid being denied boarding, as many operators have standardized their "passport-only" policy to streamline boarding and immigration protocols.