According to a Czech National Bank press release dated 8 October 2010:
As from 1 April 2011 it will not be possible to pay for goods and services with the CZK 50 [US$2.85] banknote. The Bank Board of the Czech National Bank has decided to terminate the CZK 50 banknote [Pick 17]. The note will be fully replaced in circulation by the currently used coin of the same denomination.
From 1 April 2011 to 31 March 2012, the invalid banknotes – which have a portrait of St. Agnes of Bohemia on the face side – will be exchangeable at bank branches and at branches of the Czech National Bank. From 1 April 2012 to 31 March 2017, the CZK 50 banknotes will be exchanged only by the Czech National Bank (at all its seven branches: Prague, Plzeň, Hradec Králové, Brno, Ostrava, České Budějovice and Ústí nad Labem).
The Czech National Bank has been gradually replacing the CZK 50 banknotes with coins since 2006. The number of such notes in circulation fell from 40 million at the end of 2005 to 25 million at the end of 2009, while the number of CZK 50 coins in circulation increased more than nine-fold in the same period (from 5 million to 47 million).
“The Bank Board’s main motivation in deciding to terminate the CZK 50 banknote was the lower costs of ensuring smooth currency circulation. Coins have a much longer useful life than banknotes, so they reduce the central bank’s direct expenditure on issuing money,” said CNB Bank Board member Pavel Řežábek.
The 50-crown note became part of the circulating currency as a Treasury note in 1919, shortly after the establishment of the independent Czechoslovakia. As a banknote it has been circulating in various versions since 1929 to the present. The longest period in circulation was recorded for the 50-crown note issued in 1965, which was valid until 1991. It depicted a Red Army soldier and a partisan and was designed by Václav Fiala. Treasury notes from the First Republic, especially those issued in 1919 and 1922, are most prized by collectors.
The 1994 and 1997 versions of the CZK 50 banknote are currently in circulation. The previous version (1993), which ceased to be valid in 2007, can currently be exchanged at the CNB. It will be exchangeable until 31 March 2017 only at CNB branches.”