As a general rule, two one-ways are likely to be significantly more expensive than one round-trip, easily by a factor of two or three times. Also one-ways are priced on what the markets at each starting airport can bear, so the airfares for YVR-LHR and LHR-YVR may vary wildly from each other.
Last edited by London Dude; Nov 25, 2021 at 6:00 am