Yes, swimming in Sardinia in October can still be possible, but it is no longer something you should consider guaranteed every day. The sea cools more slowly than the air, so after a warm summer water temperatures may remain pleasant well into the month.
Sunny, calm periods can feel surprisingly summery, particularly in southern Sardinia. A change in wind or a weather front, however, can quickly create very different conditions.
Where conditions may be better
Southern and south-eastern coasts often have an advantage because of their latitude and sheltered bays, but local wind direction matters more than simple north-versus-south rules. Cagliari, Villasimius and Chia are useful bases because they combine beaches with year-round services.
Alghero and northern Sardinia can also deliver excellent October days, although mistral winds become an important factor.
What to expect
October is better for travelers who enjoy variety. Beach time can be combined with archaeological sites, walking, historic towns, wineries and inland events. Even when swimming conditions are poor, the island offers plenty to do.
Pack swimwear but also layers and a light rain jacket. Think of the beach as a valuable bonus rather than the only purpose of the trip.
For travelers comfortable with that flexibility, October can reveal one of the quietest and most enjoyable versions of Sardinia.
