Most routes are valid for travel from October through the end of March, excluding peak holiday travel in late December and early January. A few routes also have availability in August or September.
For the cheapest fares, travel to Paris Sundays through Wednesdays, and return from Paris Tuesdays through Fridays. A handful of routes also have fares of just a few dollars more for travel on the weekends.
A Saturday night or 7-night stay is required depending on the route.
This sale is unadvertised and fares may jump at any moment.
These are Basic Economy or Economy Light fares, which include a carry-on bag plus a small personal item. A checked bag costs $60 each way.
Seats will be assigned at random upon check-in for these prices. You may be able to pay a fee to choose a specific seat.
The upgrade to a standard Economy fare ranges from $120-$180 roundtrip. It varies by dates, airline, and route. This type of fare includes one free checked bag, advanced seat assignments, and allows ticket changes/upgrades for a fee. If it's only $120 more and you bring a checked bag, it's a no brainer to upgrade to the standard Economy fare.
Norwegian may have some lower fares in certain markets. Norwegian's LowFare includes a carry-on bag and personal item with a max combined weight of 22 lbs. and a $50 checked bag fee.
As an example, I found a flight departing Atlanta ATL on Wednesday, November 20, returning from Paris CDG on Wednesday, November 27, for $490 roundtrip.