I am placing this here rather than in the British Airways forum, because the issue is really of wider interest than just to those who fly British Airways. In fact, those who fly British Airways might be aware of this.

I have noted that British Airways frequently has very cheap sale fares in the winter, seemingly far cheaper than the other airlines. Apparently the key to their cheap advertised fares is that compared to the other airlines,they had far more in surcharges. This can easily be seen by looking at fares on Orbitz.

For example, checking from Los Angeles to London Heathrow departing on February 15, returning on February 22 shows a base fare on British Airways of $248 round-trip. However, the total fare, including the Orbitz surcharge, is $478, or $230 over the base fare. American has a fare of $475 on the same route, but the surcharges are only $120, United has a base fare of $432 with additional surcharge of $120. While in this particular instance the British airways total fare still comes out cheaper, they are burying a lot more of their actual fair in hidden surcharges, which allows them to advertise prices which are far far cheaper than the other carriers, went back there and not.

I have checked this at other times when British Airways waswas not having a sale, and the total price was identical to that charged by United and American, while British Airways still had similarly deceptively low-priced base fares.

All the above examples are for nonstop flights, so there would be no difference in government assessed fees because of different connecting points.

The point of the story - when comparing fares, you cannot assume that all airlines add on the same surcharges to the base fare, and the only way to really comparison shop is to get the total price.