Cheapest return flights from Chicago to Porto in September from $472

Best time to book flights for Chicago (ORD) to Porto (OPO) flights at AirHint

AirHint found the following cheapest return flights from Chicago (ORD) to Porto (OPO) in September 2025 (see full year).

Return flights

15 Sep - 01 Oct TAP
24 Sep - 08 Oct Air Canada
24 Sep - 10 Oct Air Canada
22 Sep - 29 Sep British Airways
30 Sep - 07 Oct Lufthansa
03 Sep - 09 Sep Air Canada
09 Sep - 16 Sep United
20 Sep - 04 Oct Turkish Airlines
18 Sep - 25 Sep TAP
14 Sep - 21 Sep Icelandair
01 Sep - 08 Sep British Airways
20 Sep - 27 Sep TAP

Also check the deals for one-way flights from Chicago to Porto 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.

Book a cheap hotel in Porto

Cheap car rent in Porto