Originally Posted by KARFA

The charges will be the extra carrier surcharge from WTP to CW, so for LHR-JFK that would be about £50-60. There is no fee for doing a UuA.

Be careful as a known issue for a longhaul-longhaul multiple leg booking is that the agent may try and charge you the extra carrier surcharge for both legs even if you are only UuA'ing one leg. This is to do with how the agent sees the cost when they process your UuA. If they are quoting siginficatly more than £60 query it.