10 Colones

The Banco Central de Reserva de El Salvador was established in 1934 following the collapse of the private banking system during the global depression — previously, note issuance had been fragmented across competing commercial banks. By the 1962–1966 period, the Central Reserve Bank had consolidated monetary control entirely, and Thomas De La Rue's involvement reflects the institution's preference for prestige security printing over regional alternatives available through the 1950s and 60s.

De La Rue supplied El Salvador across multiple series during this period, and P#103 shares its general printing architecture with several concurrent denominations — which occasionally creates confusion in date attribution when signatures change mid-run without a new pick number assigned.