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

Sunday, September 6th, 2026

4 round-trip options

Returning
Sat, Sep 12, 20266 Day Trip
$694 USD
Returning
Mon, Sep 14, 20268 Day Trip
$694 USD
Returning
Thu, Sep 17, 202611 Day Trip
$717 USD
Returning
Sat, Sep 19, 202613 Day Trip
$694 USD