5 Pesos

The Banco de Buenos Ayres was established in 1822 as Argentina's first proper bank of issue, founded partly on the model of the Bank of England and with direct involvement from the provincial government of Buenos Aires. It issued paper currency backed by metallic reserves — a system that collapsed spectacularly in 1826 when the bank was absorbed into the newly created Banco Nacional, whose over-issuance triggered a currency crisis that persisted for years.

Notes from the 1827–1828 window therefore circulated during an acute monetary emergency, not routine commerce. The Banco Nacional itself failed by 1836, and surviving Banco de Buenos Ayres paper from this transitional period is genuinely scarce.