100.000 Réis

The 100.000 Réis was the highest denomination Banco de Portugal produced in this period — a note whose value was so large it functioned almost exclusively as an instrument of commercial settlement between merchants and financial houses rather than anything approaching everyday use. Most Portuguese at the time had never seen, let alone handled, one.

Printing in Lisbon rather than London or Paris was a deliberate institutional choice, keeping production under close domestic supervision, though it meant the engraving quality could not match what firms like Perkins Bacon were simultaneously producing for other European issuers.

The guilloche underprint was the primary anti-counterfeiting measure — a meaningful limitation given the denomination at stake.