Tax and Fees always seem higher on Business Class and First Class Tickets - Doesn't the British Government now charge a higher departure tax for business and first passengers. What happens when people are upgraded? Are the higher fees and taxes applicable?

APD has indeed got higher rate for premium cabins (as an aside, as these were defined as being separate cabins on an aircraft, Concorde counted as 'economy' for the purposes of this duty). Whenever I've been upgraded, though, the cost has been borne by the airline.

Same with re-routing to higher-tax airports (e.g. LCY).

So people flying Concorde avoided Tax / - not sure whether I find that funny or maddening - The exremely rich will always find ways of avoiding to pay their taxes!

No, I think it's more a case of the lawyers will always find ways of failing to catch everything that they should catch.

When the premium cabin rate of air passenger duty was introduced (I can't remember if it was there right from the inception of the idea), the lower rate was payable by passengers in the lowest service class/cabin on the aircraft; everyone else paid the premium rate. If there was only one such class/cabin on the aircraft, everyone paid the lower rate.

I'll bet that the departmental lawyers who drafted the legislation either didn't appreciate that a single premium-class only aircraft like Concorde would fall into that definition, or alternatively decided that it wasn't worth it (for 14 flights a week, carrying a maximum of 100 passengers each) to try to come up with some more convoluted definition that would compare the service in the cabin on the single-class aircraft with the service in the cabins on other aircraft operated by the same airline.

As I understand it, you should still be able to use the benefit of this definition by flying on the single premium-class only aircraft being operated from Stansted at the moment. And if you fly MaxJet, you don't even have to be particularly rich to take advantage of it.

I've been told AA now charges the passenger; I know UA does not.

If you request an upgrade from economy to a premium class..... it is more likely that the airline will include the additional taxes and any other fee. If the upgrade is from a premium class to a better class.... there is no additional taxes.

There is no differential tax for different airports in the UK such as London City or any other. The tax is the same whichever airport you use, except that there is an exemption for "Highland and Island" remote airports in Scotland.

My sloppy wording. Should be 'fees', not tax.