From the USA to Europe are only a few Day-flights Available they mostly go to London Heathrow Airport.
there are two seasonal daylight routes via Iceland.

British Airways BA180
07:55 EWR New York Newark
19:35 LHR London-Heathrow

United UA934
08:45 EWR New York Newark
20:35 LHR London-Heathrow

Following Codeshares are available

American Airlines AA6972 
07:55 EWR New York Newark
19:35 LHR London-Heathrow

Austrian Airlines OS7798
08:45 EWR New York Newark
20:35 LHR London-Heathrow

Lufthansa LH7818
08:45 EWR New York Newark
20:35 LHR London-Heathrow

Brussels Airlines SN9051
08:45 EWR New York Newark
20:35 LHR London-Heathrow

Air Canada AC5874
08:45 EWR New York Newark
20:35 LHR London-Heathrow

British Airways BA178
08:05 JFK New York John F Kennedy
19:50 LHR London-Heathrow

Virgin Atlantic VS26
08:15 JFK New York John F Kennedy
20:05 LHR London-Heathrow

American Airlines AA142
10:20 JFK New York John F Kennedy
22:10 LHR London-Heathrow

Following Codeshares are available

Finnair AY5478 
08:05 JFK New York John F Kennedy
19:50 LHR London-Heathrow

American Airlines AA6939
08:05 JFK New York John F Kennedy
19:50 LHR London-Heathrow

Iberia IB7377
08:05 JFK New York John F Kennedy
19:50 LHR London-Heathrow

Air France AF9656
08:15 JFK New York John F Kennedy
20:05 LHR London-Heathrow

KLM KL4825
08:15 JFK New York John F Kennedy
20:05 LHR London-Heathrow

Delta DL5996
08:15 JFK New York John F Kennedy
20:05 LHR London-Heathrow

Finnair AY4036
10:20 JFK New York John F Kennedy
22:10 LHR London-Heathrow

British Airways BA1594
10:20 JFK New York John F Kennedy
22:10 LHR London-Heathrow

Iberia IB4614
10:20 JFK New York John F Kennedy
22:10 LHR London-Heathrow

jetBlue B64462
10:20 JFK New York John F Kennedy
22:10 LHR London-Heathrow

British Airways BA238
07:55 BOS Boston Logan International
19:35 LHR London-Heathrow

Following Codeshares are available

Finnair AY5438
07:55 BOS Boston Logan International
19:35 LHR London-Heathrow

Iberia IB7414
07:55 BOS Boston Logan International
19:35 LHR London-Heathrow

American Airlines AA6981
07:55 BOS Boston Logan International
19:35 LHR London-Heathrow

United UA122 
08:25 IAD Washington Dulles 
20:50 LHR London-Heathrow 

Following Codeshares are available 

Lufthansa LH9227 
08:25 IAD Washington Dulles 
20:50 LHR London-Heathrow 

Austrian Airlines OS7804 
08:25 IAD Washington Dulles 
20:50 LHR London-Heathrow 

Air Canada   AC5338 
08:25 IAD Washington Dulles 
20:50 LHR London-Heathrow 

Brussels Airlines SN122 
08:25 IAD Washington Dulles 
20:50 LHR London-Heathrow

American Airlines AA90
08:18 ORD Chicago O'Hare International
22:10 LHR London-Heathrow

Following Codeshares are available

Finnair AY5752 
08:18 ORD Chicago O'Hare International
22:10 LHR London-Heathrow

British Airways BA1541
08:18 ORD Chicago O'Hare International
22:10 LHR London-Heathrow

Iberia IB4212
08:18 ORD Chicago O'Hare International
22:10 LHR London-Heathrow

Icelandair FI612
13:00 JFK New York John F Kennedy 
22:50 KEF Reykjavik Keflavik
(this is a Seasonal route and might not be avalible all year)

Following Codeshares are available

jetBlue B65679
13:00 JFK New York John F Kennedy 
22:50 KEF Reykjavik Keflavik

Icelandair FI634
12:35 BOS Boston Logan International
21:50 KEF Reykjavik Keflavik
(this is a Seasonal route and might not be avalible all year)

Following Codeshares are available

jetBlue B65634
12:35 BOS Boston Logan International
21:50 KEF Reykjavik Keflavik

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