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[edit] Taxes on Upgrades

Certain countries levy taxes that vary depending on the class of service. When upgrading a flight, AA will collect the tax difference from you.

[edit] France

France has an "AIR PASSENGER SOLIDARITY TAX", code IZ, that increases from EUR10.00 in economy (or premium economy) to EUR40.00 in business or first for transatlantic flights.

The difference is therefore EUR30.00.

Note that it does not apply "WHEN TRANSITING FRANCE WITHIN 24 HOURS".

[edit] United Kingdom

The U.K. has the "AIR PASSENGER DUTY APD", code GB, that increases from GBP40.00 in economy to GBP80.00 in business or first (or premium economy) for transatlantic flights.

The difference is therefore GBP40.00

Note that it does not apply with "24 HOUR TRANSIT TIME APPLIES TO INTERNATIONAL FLIGHTS, FOR DOMESTIC FIGHTS THE CONNEX TIME IS 6 HOURS, EXCEPT WHEN ARRIVAL IS AT 1700 HRS OR LATER THEN DEPARTURE IS VALID BY 10AM NEXT DAY"; however, the connecting flight must be on the same ticket for the tax to be waived.