No, the Disco Bus usually stops at the end of September. In October you’ll need taxis, hire cars, or regular buses to get around at night.
Yes. The sea remains warm from summer (around 22–23°C), so swimming is still comfortable well into October.
Most do, especially in Ibiza Town, Santa Eulalia, and San Antonio. Some seasonal venues close by mid or late October, but you’ll still find plenty of dining options.
Yes, but October is when they host their big closing parties. Expect packed weekends at clubs like Amnesia, Ushuaïa, and Pacha until mid-October, after which nightlife slows.