Private car
The straightforward version. Eleven to thirteen hours, best split across two days with a night at Bajawa or Ruteng.
Photo: Felix Dance / Wikimedia Commons, CC BY 2.0.
The transfer
Why the Riung–Labuan Bajo boat transfer people search for does not exist, and what the real options are.
There is no scheduled boat between Riung and Labuan Bajo — the connection is overland via Bajawa and Ruteng, roughly 340 km and eleven to thirteen hours of driving.
The options
The honest comparison, including the one most people end up taking.
The straightforward version. Eleven to thirteen hours, best split across two days with a night at Bajawa or Ruteng.
Photo: Felix Dance / Wikimedia Commons, CC BY 2.0.
Cheapest and slowest. Riung to Bajawa, Bajawa to Ruteng, Ruteng to Labuan Bajo — a genuine two-day journey.
Photo: Serenade / Wikimedia Commons, CC BY-SA 3.0.
South to Ende, then fly. Saves the worst of the driving when the thin schedules cooperate.
Photo: Jakub Hałun / Wikimedia Commons, CC BY 4.0.
Why the confusion
Chartered vessels do sometimes run long coastal legs that touch both ends, which is where the idea of a Riung–Labuan Bajo boat transfer comes from.
That is a private charter over several days, not a transfer. As a way of getting from A to B it costs many times what the road does.
Riung boats are arranged locally, at the pier. For the Komodo leg or a full Flores itinerary, the reservations desk answers on WhatsApp.