Getting to Ios can be a bit of a trek but it’s well worth it for a little bit of effort! There is no airport on Ios, so the island is only accessible by ferry. Most people choose to fly directly to Athens or Santorini and then take the ferry to Ios Island.
Boats and ferries to Ios Greece depart from Piraeus port or Rafina in Athens (from and to Ios Island Greece). During the summer months ferries to Ios run pretty frequently – there are normally about 2 to 3 ferries each day. It takes about 4 to 7 hours depending on which ferry to Ios you are on.
You may also need to spend a night in Athens depending on what time your ferry leaves at so here is a link to hotels near Piraeus Port.