20 Mil Reis

The Banco Nacional Ultramarino occupied an unusual position in Portuguese colonial finance — chartered in Lisbon in 1864, it held note-issuing rights not just for Portugal's African and Asian territories but also, at various points, for metropolitan Portugal itself during periods when the Banco de Portugal's monopoly was contested. By 1909, the BNU was the primary circulation bank for Portuguese Guinea, São Tomé, Cape Verde, Mozambique, Angola, and several Asian possessions, meaning a single series of notes had to function across wildly different economic environments.

The 1909 series was printed at the Casa da Moeda in Lisbon. Surviving examples frequently show ink oxidation along fold lines — a known issue with this printing run attributed to the cotton stock used.