Originally Posted by
SFO777
The one-way vs. round-trip fare comparison will vary by market and degree of competition. Most markets are indeed one-way times 2. But some markets require a round-trip for the cheapest fares. United seems to be the one airline that socks you one way on uncompetitive city pairs. For instance, DEN-IAH next March is $293 RT, but $384 for a one way ticket.
I used to see this frequently on US for VPS-DCA. RT would often be $200-260, but OW would be ~$600. It was only operated once or twice a day, and I couldn't leave work in time on Friday to catch the VPS-DCA departure. DCA-VPS was well-timed, but would cost $600 OW. I could have bought tickets in the opposite order, but I didn't want to go through that much trouble for 2+ hours on a CRJ2 when I could easily connect through ATL and consistently pay $222 RT. Alas, I no longer live in FL, and that route is gone now with AA/US having to divest at DCA.