The rupee (Sinhalese: රුපියල්, Tamil: ரூபாய்) (signs: රු, Rs, ரூ; code: LKR) is the currency of Sri Lanka, divided into 100 cents. It is issued by the Central Bank of Sri Lanka. The abbreviation is generally Rs., but SLRs. is occasionally used to distinguish it from other currencies also called rupee.

The British pound became Ceylon's official money of account in 1825, replacing the Ceylonese rixdollar at a rate of 1 pound = 13 ¹⁄₃ rixdollars, and British silver coin was made legal tender. Treasury notes denominated in pounds were issued in 1827, replacing the earlier rixdollar notes. Rixdollar notes not presented for exchange were demonetized in June 1831.

The Indian rupee was made Ceylon's standard coin on 26 September 1836, and Ceylon reverted to the Indian currency area. Pound-denominated treasury notes continued to circulate after 1836, along with the rupee. The legal currency remained British silver and accounts were kept in pounds, shillings and pence. However, payments were made in rupees and annas at the "fictitious par" (fixed accounting rate) of 2 shillings per rupee (i.e., 1 pound = 10 rupees).

The Bank of Ceylon was the first private bank to issue banknotes on the island (1844) and Treasury notes were withdrawn in 1856.

The Indian rupee was formally established as the unlimited legal tender 18 June 1869. The rupee was decimalized 23 August 1871. Thus, the rupee of 100 cents became Ceylon's money of account and sole legal tender effective 1 January 1872, replacing British currency at a rate of 1 rupee = 2 shillings 3 pence.

In 1872, copper ¹⁄₄, ¹⁄₂, 1 and 5 cents coins dated 1870 were introduced, followed in 1892 by silver 10, 25 and 50 cents. Production of the ¹⁄₄ cent ceased in 1904. The large, copper 5 cents coin was replaced in 1909 by a much smaller cupro-nickel coin which was square with rounded corners. In 1919, the fineness of silver used was reduced from .800 to .550.

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