Fishguard to Rosslare is the quickest ferry crossing to Ireland from Great Britain. This route takes approximately 2 hours 15 minutes. Stena Line operates this route with 14 weekly sailings.

The quickest ferry crossing between Ireland and the UK is the route from Dublin to Holyhead (Wales) when using a "fast ferry" service. The Dublin Swift, operated by Irish Ferries, is a high-speed catamaran that can complete the crossing in approximately 2 hours and 15 minutes. Standard conventional ferries on this same route, such as those operated by Stena Line or the larger Irish Ferries vessels (like the Ulysses), typically take around 3 hours and 15 minutes. Another very fast option is the Belfast to Cairnryan (Scotland) route, where the Stena Line "Superfast" vessels complete the journey in about 2 hours and 15 minutes. While there were once even faster "HSS" (High-speed Sea Service) vessels that could cross in 90 minutes, these were largely retired due to high fuel costs. For 2026 travelers, the Dublin-to-Holyhead fast ferry remains the gold standard for speed, especially for those looking to reach London or the Midlands quickly via the well-connected A55 road or the Holyhead railway station.