As highlighted by Scott's Cheap Flights, you can also find the layover deal on flights from the US to Oslo.
To track down the best price, use Google Flights or another service to find a roundtrip flight from your city to London or Oslo using Icelandair. After you find your date, make the date of the original return trip a flight to Reykjavik using Google Flights' multi-city search. You can probably shave a few dollars off that price by inputting the same information into Momondo. For instance, the Seattle flight came to $339 through Google Flights, but that same trip is $335 through Momondo.
Best of all, Icelandair isn't a budget airline like WOW or Norwegian, both of which can have great deals, but there are a lot of hidden expenses. With Icelandair, you won't get all those luggage and add-on fees.
Prices can and do change quickly, so jump on it if you want to take advantage. Not all layovers suck. In fact, sometimes they're worth hunting down.
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