surcharge
sur-charge
verb
To add an extra charge or payment to the usual cost of something.
"Some shops surcharge customers paying by card."
noun
An additional charge or payment added to the usual cost of something.
"There is a small surcharge for using a credit card."
Thesaurus
Synonyms: pluck, soak, hook, rob, gazump, plume, fleece, overcharge, overload
Antonyms: undercharge