AirHint found the following cheapest return flights from Chicago (MDW) to Lisbon (LIS) in July 2025 (see full year).

Return flights

11 Jul - 24 Jul	Delta
10 Jul - 17 Jul	Delta
17 Jul - 25 Jul	Delta
09 Jul - 16 Jul	Delta
15 Jul - 23 Jul	Delta
15 Jul - 28 Jul	Delta
11 Jul - 19 Jul	Delta
05 Jul - 10 Jul	Frontier Airlines
22 Jul - 12 Aug	Porter Airlines (Canada) Ltd
17 Jul - 21 Jul	Porter Airlines (Canada) Ltd
10 Jul - 21 Jul	Delta
22 Jul - 05 Aug	Porter Airlines (Canada) Ltd
28 Jul - 04 Aug	Porter Airlines (Canada) Ltd
21 Jul - 04 Aug	Porter Airlines (Canada) Ltd
22 Jul - 07 Aug	Porter Airlines (Canada) Ltd
26 Jul - 07 Aug	Delta
24 Jul - 09 Aug	Delta

Also check the deals for one-way flights from Chicago to Lisbon in July.

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 Lisbon

Cheap car rent in Lisbon

Cheapest return flights from Chicago to Lisbon in July from $799

Return flights