Washington (IAD) to Porto (OPO) flight deal in economy from $739

Friday, September 4th, 2026

5 round-trip options

Returning
Thu, Sep 10, 20266 Day Trip
$1,342 USD
Returning
Sat, Sep 12, 20268 Day Trip
$1,472 USD
Returning
Sun, Sep 13, 20269 Day Trip
$1,402 USD
Returning
Tue, Sep 15, 202611 Day Trip
$1,342 USD
Returning
Thu, Sep 17, 202613 Day Trip
$1,286 USD