Virgin Atlantic and codeshare partner Delta Air Lines are having some good price drops on nonstops to London in a quirky combo of an advertised and non-advertised sale.

Virgin is promoting an official sale on daily flights during January 9 through March 31, 2019, from many of its American gateways onward to London. But when ticketing these fares, prices drop further below what they are advertising. When searching for these fares, you will notice that the prices on these itineraries fall dramatically on the final booking screen and cost even less when booking on the Delta website. As an example, I've provided a screenshot below. It's like a sale on top of another sale!

The hitch is, all fares book into Virgin and Delta's corresponding Light or Basic Economy fare buckets, meaning you'll only be allowed standard sized carry on baggage. Checked baggage will cost an additional $60 each way, which will significantly increase the price. Do keep in mind these are both full-service airlines, so meals, in-flight entertainment, and drinks will still be included. As opposed to flying on Norwegian who charge extra for those amenities and also serve many of these routes at a similar price point.

This sale is set to expire tomorrow at midnight October 3, 2018, so it's best to book before then as these fares might jump in price, given the unadvertised element of these fares. Delta allows a 24-hour cancellation grace period if you book a trip and change your mind overnight.  

Nonstop sale fares include:

Boston to London-LHR $402 roundtrip

New York to London-LHR $422 roundtrip

Newark to London-LHR $422 roundtrip

San Francisco to London-LHR $422 roundtrip

Orlando to London-LGW $422 roundtrip

Las Vegas to London-LGW $422 roundtrip

Los Angeles to London-LHR $462 roundtrip

Miami to London-LHR $462 roundtrip

Seattle to London-LHR $545 roundtrip

As shown below, I found seats departing BOS on Friday, January 18 and returning from LHR on Saturday, January 26, 2019. Other dates are widely available.