Guernsey: Coins Issued and Used

Until the early 19th century, Guernsey used predominantly French currency. Coins of the French livre were legal tender until 1834, with French francs used until 1921.

In 1830, Guernsey began production of copper coins denominated in doubles. The double was worth 1/80 of a French franc. The name "double" derived from the French "double deniers", although the value of the coin was equal to the liard (3 deniers piece) still circulating. Coins were issued in denominations of 1, 2, 4 and 8 doubles. The 8 double coin was a "Guernsey penny", with twelve to the "Guernsey shilling" (worth 1.2 francs). However, this shilling was not equal to the British shilling (worth 1.26 francs, as the exchange rate according to the respective gold standards was 25.22 francs = 1 pound sterling).

Banknotes were also produced by the States of Guernsey from 1827, denominated in pounds.

In 1848, an ordinance was passed that the pound sterling should be legal tender at a value of £1 1s 3d (2040 doubles). This was rescinded two years later and French currency, supplemented by local issues, continued to circulate. In 1870, British coins were made legal tender, with the British shilling circulating at 12½ Guernsey pence. Bank of England notes became legal tender in 1873. In 1914, new banknotes appeared, some of which carried denominations in Guernsey shillings and francs.

After the First World War, the value of the franc began to fall relative to sterling. This caused Guernsey to adopt a pound equal to the pound sterling in 1921. For amounts below 1 shilling, the conversion rate of 1 Guernsey penny (8 doubles) = 1 British penny applied, allowing the Guernsey coins to continue to circulate. For amounts above 1 shilling, an exchange rate of 21 Guernsey shillings to the pound sterling was used, applying an approximation to the pre-war exchange rate of 25.2 francs = 1 pound sterling, rather than the exact rate of 25.22. This conversion increased the value of the double from 1⁄2016 to 1⁄1920 of a pound. The WWI issues of banknotes were overstamped with the word "British" to indicate this change. New banknotes and British silver coinage circulated alongside the double coins, with 3 pence coins minted specially for Guernsey from 1956.

In 1971, along with the rest of the British Isles, Guernsey decimalized, with the pound subdivided into 100 pence, and began issuing a full range of coin denominations from ½p to 50p (£1 and £2 coins followed later).