Very interesting. I did a bit of digging on this. Just to clarify a few things as some previous posters have made incorrect assumptions.
- This does not appear to be a codeshare situation. The flights on united.com show up as AC marketed and operated flights.
- The cheaper $166 fares show up when searching on ITA matrix, so is legit.
- This is not a situation where united.com is combining 2 separate fares. This is fare basis L7U9CBA and the allowable routings per ExpertFlyer are:
1. YTO-YYG/YSJ/YQM/YOW/YMQ/YFC-YHZ
2. YTO-YOW-YMQ-YHZ
3. YTO-YHZ
Unfortunately the fare guarantee doesn’t apply as the routings and flight numbers shown on aircanada.com and the cheaper alternative must be identical. The AC site isn’t even showing those routing options.
Whether AC.com is being deliberately deceptive, I can’t say. It could simply be that the website is setup to exclude connections in smaller airports.
i haven’t tried a multi-city booking on Air Canada site. I wonder if that would show the lower pricing.