1 Guinea = 1 Pound 1 Shilling Sterling

The guinea denomination — 21 shillings rather than 20 — was a peculiarity of Scottish private banking practice in the late eighteenth century, used partly to sidestep English restrictions on notes under £1 sterling and partly because guinea-denominated contracts were common in professional and commercial transactions. The Royal Bank of Scotland was chartered by the Crown in 1727, making it one of only two Scottish banks to hold a royal charter, and its notes from this period carried genuine legal weight in a market still crowded with smaller provincial issuers of questionable solvency.

By 1792, hand-to-hand guinea notes were already declining; the denomination was largely phased out across Scottish banking within a decade.