Originally Posted by NickZ
Plenty of cheap options these days for one way flights.
Level (Owned by the same people that own BA and Iberia)
Others I'm sure depending on your starting point.
Level just announced direct flights from Boston to Paris for next year but they have other flights. Looks like Boston one way starts at €140
Just a heads up - as a road warrior for many years I learned that one-way tickets raise red flags with the airline/airport security people and you might attract extra security checks. No reason not to buy one but just be aware you might have longer check-in times