Wow Air has a Presidents Day sale for $45 tickets one way to Iceland from Boston BOS, Baltimore BWI, Newark EWR and Detroit DTW. My searches indicate this can be booked as a one way ticket for $45 all-in flying with only an underseat carry-on. Lowest round trip I found was $145 for Baltimore to Reykjavik round trip.
Add $45 each way for a full-size carry-on or $55 for one checked bag.
Add $7 each way for a self-selected seat assignment at booking.
Wow Air Detroit DTW – Reykjavik KEF
$45.00 one way Mon March 25
Wow Air Baltimore BWI – Reykjavik KEF – BWI
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