It may seem a tad premature to begin planning your summer vacation in March, but summer fares to Europe are shaping up to be some of the lowest we've ever seen.

How cheap is cheap? We’re talking transatlantic flights for under $600, and many of these are nonstop. That's quite a drop from the $1,200+ economy fares we typically see in the summer months.

And no, these cheap summer flights aren't all on budget carriers, though they’ve certainly had a hand in bringing down prices on legacy carriers.

Of course, another reason summer fares may appear lower at first glance this year is the sudden increase in international basic economy seats. I’ve tried to avoid including these with the exception of Delta, which, unlike other carriers, does include carry on baggage in basic economy. That, along with an additional personal item/small bag, is often enough for light packers and budget travelers.

Below are a few examples of what we’ve spotted recently from airports across the U.S.

Newark to London $523 round-trip, nonstop, on Primera Air

This is a new route from Primera. We found seats departing EWR on Friday, July 6, returning from STN on Friday, July 13. Carry ons under 22 lbs are free of charge.

You’ll find more great fares from Newark EWR listed here.

New York to Amsterdam $516 round-trip, nonstop, on United

Checking United, we found seats departing JFK on Tuesday, August 7, returning from AMS on Wednesday, August 15. This appears to be the cheapest summer option, with higher fares available in June and July.

See our New York JFK fare listings for cheap fares like this one.

Miami to Dublin $516 round-trip, nonstop, on Aer Lingus

Depart MIA on Sunday, August 12, return from DUB on Sunday, August 19. This Aer Lingus fare appears to be available only for a few dates in August, but July dates can be booked for $628.

Check out our Miami MIA listings for a look at similar finds.

Minneapolis to Paris $590 round-trip, nonstop, on Delta

Yes, this is a basic economy fare, but as I mentioned above, Delta’s version of basic economy includes a carry on bag. But be sure to cram all that you can in that one carry on because Delta’s checked bag fee for this trip is a whopper, at $60 each way.

We found seats departing MSP on Monday, August 13, returning from CDG on Tuesday, August 21. Other dates are available for travel throughout August.

Visit our Minneapolis MSP listings for more low fares.

Los Angeles to Paris $524 round-trip on Air Canada

Searching United, we found seats departing LAX on Wednesday, August 15, returning from CDG on Thursday, August 23. This flight is operated by Air Canada and connects via Vancouver outbound and, on the return, Montreal. Similar fares are available throughout August.

See our Los Angeles LAX listings for a look at current fares.

San Francisco to London $597 round-trip, nonstop, on United

Depart SFO on Monday, August 13, return from LHR on Tuesday, August 21. Seats are scarce at this price, with greater availability in late August for $625 nonstop.

See our San Francisco SFO fare listings for a complete look at current finds.