I don't know if anyone has heard of or tried WOW airlines. They are a low-cost airline out of Iceland, and like Icelandair, offer flights with a stopover option in Reykjavik. But less expensive.
I traveled them to Iceland last summer, in July-Aug, and my airfare was $623 each from Baltimore to Reykjavik, non-stop, round trip. Yes, you pay a little extra for checked bags and bigger seats. It still came to a total of $670 each with all that. Much less than the Icelandair option of $1300 per ticket.
They offer travel to Ireland as well, and I just checked late May tickets from Baltimore, at $770 round trip. It might be an option to include on airfare searches, as I don't believe they are in most consolidators like Kayak. Just FYI!
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May the light be your guide and the darkness be your comfort!
Any potential savings I found were quickly nullified by their high baggage fees. Factor in food/beverage and lack of entertainment, limited airports and, I'll pass. It is an interesting change in the way we fly. Air Canada Rouge is another no frills airline that seems to show up on many search engines. So is Norwegian airlines. The stage seems to be set for Ryan air to enter the market.
My fares to Iceland in July (non-stop from Baltimore) was $630. Fees for luggage, seats, etc. brought that to about $690 each. Icelandair for a similar flight was $1100 at the lowest. There is no on-board entertainment, that is very true. But the planes were new, the seats comfortable (we paid an extra $14 each for bigger seats, and gladly!). The flight attendants were very nice, and everything was on time. The food/beverage options on board were reasonable (it was a 5.5 hour flight). I had a good burger, my husband had a nice cup of soup, we both indulged in some adult beverages :)
There are limited airports - Boston or Baltimore.
Neat factoid: Each plane is actually dedicated (via ceremony) to a Norse God. We flew on Odinn (the name is printed on the plane, you can see it as you board).
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May the light be your guide and the darkness be your comfort!
Hopefully the no frills industry will continue to grow and more airport options will become available. I remember the time when Aer Lingus flew from less airports and only on select days. Competition is good for us consumers and a welcomed sight!