Demonetization is the act of stripping a currency unit of its status as legal tender. It occurs whenever there is a change of national currency. The current form or forms of money is pulled from circulation and retired, often to be replaced with new notes or coins. Sometimes, a country completely replaces the old currency with new currency.

The opposite of demonetization is remonetization, in which a form of payment is restored as legal tender.

Demonetization is undertaken by nations for a number of reasons:

• to combat inflation
• to combat corruption and crime (counterfeiting, tax evasion)
• to discourage a cash-dependent economy
• to facilitate trade

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