Cheapest return flights from Denver to Ljubljana in September from $860

AirHint found the following cheapest return flights from Denver (DEN) to Ljubljana (LJU) in September 2025 (see full year).

Return flights

05 Sep - 15 Sep British Airways
26 Sep - 03 Oct Frontier Airlines

Also check the deals for one-way flights from Denver to Ljubljana in September.

Skyscanner

The deals are updated regularly. The prices may go up as tickets are purchased by other travellers. Only the cheapest flights are offered. Select a price to book and secure these cheap prices.

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