Section 10 of the technical rule sheet for the xONEx fares states:

When travel originates in a country for which a specific local currency fares is published and the ticket is sold in another country, the fare will be that published for the country of origin converted to the currency of the country of sale at the bank selling rate. The resultant fare must not be lower than from the country of sale. Exception: Not applicable for sales made and/or travel originating in Canada or when BOTH travel originates and sales are made within the European Common Aviation Area (ECAA)/Switzerland.

I have seen several posts discussing taking advantage of this "Canadian exception" of purchasing a RTW ticket in Canada when the country of origin is somewhere with cheap xONEx fares.

My question is whether the opposite is also possible: can one purchase an xONEx ticket in the UK, with Canada as the country of origin, and pay the lower UK fare rather than the higher Canadian fare?

The wording from the technical rule sheet seems to allow this ("...or travel originating in Canada"), but it's possible that I am misinterpreting the rules.

Welcome to FT flybynight123

This rule is forced by Canadian legislation.

How would this work? Does this mean it is possible to get the ex-UK fare for an itinerary not originating in the UK, but in Canada?

For example, I'm based in NYC but travel to LHR frequently. Could I buy an xONEx at the counter at LHR, travel originating at YYZ, and still pay the ex-UK fare? (making up the difference with a one-way AAward to YYZ?)

There seems to be a kicker in application here.

Buy the specifics of the quoted rule, when buying in the UK for travel ex Canada (from where there is a published fare), the Canadian rate would be converted to GBP and that fare charged, regardless of which is the higher/lower in relation to the fare from the UK.

So if the Canadian rate was lower it would be an advantage; however this is not the case currently.

IMHO it seems to be another example of sloppy wording
To what does the "Exception:" refer?

The usual interpretation is that it refers to the second sentence of the rule - "The resultant fare must not be lower than from the country of sale."
In which case the first sentence stands on its own: when the exception applies, you pay the fare published for the country of origin no matter whether that is higher or lower than the fare in the country of sale. This is what serfty is saying.

The alternate interpretation is that the exception refers to the first sentence. This seems to be the interpretation the OP is putting on it. If this were the case then it is unclear what the rule is when the exception applies. It seems to me quite a leap to then say it then means "and so you can pay the fare of the country of sale".

All would be much clearer if the rule had a paragraph marker between the first and second sentences.

However - a thought has just occurred to me - the "or travel orginating in Canada" would allow US purchasers to buy their RTW tickets in the US at the Canadian price provided the journey starts in Canada. No need then to make a separate journey north of the border just to buy the ticket. I don't recall seeing that discussed before.

This has been discussed before and you are correct, if you are buying a ticket ex-CA from the US you can do so from the US (or any country) at the CA Prices. The most recent discussion involved a CIR ticket and can be found here: http://www.flyertalk.com/forum/onewo...e-pacific.html (note posts 9-14)