Jackie - do you mean the difference between econ and premium economy. If that is the case then mainly it is seat width and pitch.
Premium econ has a pitch of 38" compared with economy of 31". The food is exactly the same although you are given a glass of champagne or bucks fizz on boarding and baileys or brandy after your hot meal.You also have a dedicated check in desk - although not at twilight check in at LGW.
Jill
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