Booking a return flight but only intending to use the outbound flight???

[NannyR]

I need to book a one way flight from Luxembourg to Leeds Bradford at the end of July. The one way price is 810 euros, return price 260 euros.
What is the worst that will happen if I book the return fight and just don't turn up for the return leg? I know that if I did it the other way round and didn't use the outward leg, they would cancel the return.
Will I be blacklisted by KLM the next time I want to book a flight???

No you'll be fine, so long as it is the return flight you jettison.

You may even be able to rebook the return and use it later - one of my team has manged to keep a return flight from the USA going for months on this basis!

You'll be fine. I have done it before, even with charter flights. You just don't turn up for the return flight.

Nanny - just so you know, I tend to fly out of Humberside rather than Leeds Bradford when I travel with KLM from Leeds; the prices are cheaper and there can be bizarrely more choice of flights despite Humberside being a teeny tiny airport.

Only useful to you if you have transport arranged at this end, though. I think public transport at Humberside is 'catching a horse in the nearby field'