But using the euro in contracts has commercial implications. For example, just because a national currency has been replaced in a legal sense does not mean that an obligation under contract to pay in that currency can be avoided, or that the obligation is altered. Fixed interest rates will not change. If a contract sets a fixed rate of interest on a debt in a currency that has been replaced for example, an outstanding loan in French francs interest will need to be paid at the same rate unless otherwise agreed. The great majority of other commercial terms in contracts, such as delivery dates, will not be affected.
Most businesses are unlikely to experience legal difficulties.
However, if you trade heavily outside the EU, you should consider checking any contracts that refer to currencies replaced by the euro, especially those which in the case of any dispute would be subject to laws other than those of the major industrial countries. Although the legal position will be clear for the great majority of contracts, the commercial implications of using the euro may be more difficult to forecast. As a new currency, the behaviour of the euro in the financial markets against other world currencies may differ from the behaviour of national currencies previously. Any change in behaviour would also affect contracts denominated in national currencies because those currencies are locked to the euro. During this period, both the euro and the national currency units will exist.