In theory, Irish and British citizens do not need to show passports when traveling on the Dublin to Holyhead Ferry, but citizens of other countries do need to show passports, so you might need to show your passport to prove that do you not need to show a passport.

Yes, in 2026, passport and ID checks at the Holyhead ferry port (connecting Wales to Ireland) have become much more rigorous. While the Common Travel Area (CTA) theoretically allows British and Irish citizens to travel without a passport, in 2026, almost all ferry operators (Stena Line, Irish Ferries) require a valid photo ID for boarding. More importantly, as of February 2026, the UK has implemented the Electronic Travel Authorisation (ETA) system for most non-Irish/non-British international visitors. This means that if you are a foreign national, your passport will be scanned to verify your digital travel permission. Additionally, in early 2026, the UK Home Office restarted Live Facial Recognition pilot programs at Holyhead to monitor border crossings. To avoid delays, 2026 travelers are strongly advised to carry a valid passport regardless of nationality, as it is the only "universally accepted" document for both the ferry lines and the 2026 digital border security systems.