Porto (OPO) to Washington (IAD) flight deal in economy from $676

Thursday, September 3rd, 2026

4 round-trip options

Returning
Wed, Sep 9, 20266 Day Trip
$681 USD
Returning
Fri, Sep 11, 20268 Day Trip
$681 USD
Returning
Mon, Sep 14, 202611 Day Trip
$681 USD
Returning
Wed, Sep 16, 202613 Day Trip
$681 USD