Some Bank of England £20 notes will not be legal tender from the end of June, Guernsey residents have been reminded.
The £20 notes being withdrawn at the end of June carry a picture of composer Edward Elgar.
The Bank of England said the notes are less likely to be accepted in shops from 1 July.
Most banks, building societies and post offices will accept them, but exchanging for non-customers is discretionary.
The Bank of England said the full value for these notes - and all other notes the bank has issued - will always be given.
The Elgar notes have been replaced with £20 banknotes bearing the picture of economist Adam Smith, which were introduced into circulation in 2007.