AirHint found the following cheapest return flights from Lisbon (LIS) to Kathmandu (KTM) in September 2025 (see full year).

Return flights

23 Sep - 19 Oct	Air Europa
22 Sep - 28 Sep	Ryanair
22 Sep - 30 Sep	Ryanair
22 Sep - 19 Oct	Ryanair
12 Sep - 20 Sep	Wizz Air
22 Sep - 01 Oct	Ryanair
22 Sep - 20 Oct	Ryanair
22 Sep - 10 Oct	Ryanair
27 Sep - 04 Oct	Wizz Air Malta
27 Sep - 12 Oct	Wizz Air Malta
08 Sep - 22 Sep	Wizz Air
22 Sep - 05 Oct	Ryanair
14 Sep - 21 Sep	easyJet
27 Sep - 18 Oct	Wizz Air Malta
16 Sep - 22 Sep	Ryanair
22 Sep - 29 Sep	Ryanair
08 Sep - 24 Sep	Wizz Air
23 Sep - 30 Sep	Ryanair
16 Sep - 23 Sep	easyJet
27 Sep - 19 Oct	Wizz Air Malta

Also check the deals for one-way flights from Lisbon to Kathmandu in September.

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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Cheapest return flights from Lisbon to Kathmandu in September from 649€

Return flights