Step 1: Sydney to Adelaide
Qantas, Virgin and Jetstar all run multiple daily flights from Sydney (SYD) to Adelaide (ADL). Flight time is around 2 hours. Sale fares from $129 one-way, walk-up over $350. Book at least a fortnight ahead for peak weekends.
Time your morning departure carefully. The earliest Sydney to Adelaide flights leave around 6 am and land before 8 am Adelaide time (Adelaide is 30 minutes behind during eastern daylight saving). That gives you all afternoon for the second leg.
Step 2: Adelaide to Kangaroo Island
Two options.
Rex to Kingscote. Walk across to the regional terminal at Adelaide Airport (5 minutes from the main domestic terminal), check in for Rex, and 40 minutes later you are on KI. Standard fare around $169 one-way. Hire a car at Kingscote airport on arrival. See the flights guide.
Drive and ferry from Cape Jervis. Pick up a hire car at Adelaide Airport, drive 90 minutes south, take the 45-minute SeaLink crossing. Slower but lets you bring a car for the whole trip. Details on the ferry page.
The connection trap
Allow at least 90 minutes between landing in Adelaide and your Rex departure on a separate ticket. The terminals are connected but bag re-check eats time. The last Rex flight out of Adelaide is mid-afternoon, so a Sydney departure after 1 pm means you are overnighting in Adelaide.
An Adelaide overnight is a feature, not a bug. Stay near the airport or in the city, eat well, and pick up the next morning's flight or ferry rested. Adelaide CBD to the airport is 15 minutes by Uber.
The honest pick from Sydney
For a 4-day weekend or longer: fly the whole way. Sydney to Adelaide on Qantas or Virgin first thing, Rex to Kingscote by lunchtime, full afternoon on the island. Reverse on the return. You lose roughly half a day each way to transit.
For a week or more, especially with two or more travellers: fly to Adelaide, hire a car, take the ferry. You spend a half-day more in transit but you avoid double car-hire bookings (one in Adelaide for the drive, one on KI), and you can build in a Barossa or Fleurieu Peninsula side trip on the way to or from Cape Jervis.
For 3 days flat from Sydney, we would push you to add a fourth. The math on a 2-night Sydney-to-KI trip is rough: you fly Friday, lose Saturday morning to the second leg, get one full day Sunday, and fly back Monday with another half-day gone. It can be done. It rarely feels worth the airfares.
Cost rough cut
Indicative return per person from Sydney, peak season.
- Fly the whole way (SYD to ADL to KGC return): around $600 to $850 per person.
- Fly to Adelaide, drive and ferry: around $500 to $700 per person plus shared car hire.
- Fly to Adelaide, book a guided KI day tour: around $400 to $550 per person.
Booking sequence
Book the Sydney to Adelaide leg first, then the Rex or ferry leg to match. Rex schedules occasionally trim with little notice, so confirm both legs before you commit to non-refundable accommodation. If you are mixing carriers, your Sydney to Adelaide booking is independent of Rex (no through-checked bags), so build the 90-minute buffer in.
Lock in the second leg here: