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

Return flights

08 Sep - 16 Sep	Qatar Airways
07 Sep - 16 Sep	Qatar Airways
09 Sep - 16 Sep	Qatar Airways
10 Sep - 17 Sep	Qatar Airways
07 Sep - 19 Sep	Qatar Airways
06 Sep - 16 Sep	Qatar Airways
11 Sep - 19 Sep	Qatar Airways
16 Sep - 29 Sep	Qatar Airways
09 Sep - 18 Sep	Spirit Airlines
21 Sep - 09 Oct	IndiGo
23 Sep - 09 Oct	IndiGo
19 Sep - 04 Oct	Spirit Airlines
25 Sep - 27 Sep	Spirit Airlines

Also check the deals for one-way flights from Houston 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.

Book a cheap hotel in Kathmandu

Cheap car rent in Kathmandu

Cheapest return flights from Houston to Kathmandu in September from $1071

Return flights