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

Sunday, September 27th, 2026

4 round-trip options

Returning
Sat, Oct 3, 20266 Day Trip
$681 USD
Returning
Mon, Oct 5, 20268 Day Trip
$684 USD
Returning
Thu, Oct 8, 202611 Day Trip
$681 USD
Returning
Sat, Oct 10, 202613 Day Trip
$682 USD