For backstory, I had a voucher that was expiring in December and had a rough idea of when/where I'd be flying in July, so I just picked some days and booked a RT.
Now that the time is nearer, I'm thinking I'd probably rather stay a little longer and also fly back from a different city making it an open jaw. Until I ended up with the voucher I had just planned on using my miles, so I kind of hate to shell out $200 for a change fee. I was wondering what would happen if I just missed that return flight and used miles on a 1 way?
Airline is United if it makes a difference.
I had that happen when the airline did not scan my ticket correctly and they thought I had not boarded the flight. What they did was to cancel my return flight. When I was trying to go home on that Friday I could not get the reservations system to work because they swore that I had not flown to Chicago.
They fought really hard to say that I was "not" in Chicago. I had to escalate it up two levels to a manager and finally out of frustration I said that since I had paid extra for a missed flight refund that I wanted the entire refund for my flight that "I did not" take.
That got their attention; giving back money would be a bad thing. Suddenly they fixed the problem.
What was really surprising was that when they had come through the cabin to get a headcount they somehow screwed that up. The plane should of never taken off if there was an undocumented passenger on board.
If you miss the first leg but call the carrier to tell them you still need the second leg, they won't cancel it. At least that was my experience with United. Delays on my first leg caused me to fly American instead of United to get to my destination, so I called United and told them I was flying American out to my destination but still needed the United booking to get back home. It worked fine.
I've booked round trip on United but then needed changes on the return flight and realized it was cheaper to book a new return flight on American rather than changing the return flight on United. So I just booked a new flight on American and canceled my United return leg. It wasn't refundable so I didn't get any credit on United. Another alternative would be to not show up for the return leg. I canceled in advance so that United could rebook and make some money even though they weren't giving me a refund. I figured that United could use all the help it could get since that airline is the worst-run carrier of the 3 legacy carriers I still book on United when I can as they do upgrade me quite a bit, so I try really, really hard to make United work for me. I guess I am a glutton for punishment