20 Francs

Pick 111 spans the full run of the German occupation and into the postwar settlement, which tells you something about Belgium's monetary situation — the Banque Nationale continued issuing notes under occupation, and this series circulated continuously through Liberation without immediate replacement. The liberation didn't trigger an instant reissue; old notes kept moving while the authorities worked through the 1944–45 currency reform that eventually targeted the inflation-bloated supply.

The reform, driven by Finance Minister Camille Gutt, was abrupt: in October 1944, all notes had to be declared and exchanged at strict limits. Most circulating 20-franc notes from this series were surrendered then, which suppresses the supply of used examples dated to the early occupation years.