AirHint found the following cheapest one-way flights from Porto (OPO) to London (STN) in September 2025 (see full year).

One-Way flights

23 Sep	Ryanair	direct
19 Sep	Ryanair	direct
17 Sep	Ryanair	direct
25 Sep	Ryanair	direct
16 Sep	Ryanair	direct
10 Sep	Ryanair	direct
27 Sep	easyJet
18 Sep	Ryanair	direct
14 Sep	Ryanair	direct
13 Sep	easyJet

Also check the deals for return flights from Porto to London 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 one-way flights from Porto to London in September from $39

One-Way flights