The sum (Uzbek: soʻm, сўм [som]; ISO code: UZS) is the official currency of Uzbekistan.

The word sum (alternatively transliterated "som" or "soum") means "pure" in Kazakh, Kyrgyz, Uyghur and Uzbek, as well as in many other Turkic languages.

All notes had the Coat of arms on the obverse, and Sher-Dor Madrasah of the Registan in Samarkand on the reverse.

All of the denominations share the same designs: the Coat of arms of Uzbekistan on the front and the madrasahs on Registan Square in Samarkand.

Back in 2019, a new largest denomination was issued, the 100,000-sum banknote (as of October 2019 worth US$10.55), which made the situation easier.

The smallest denomination, the 1 tiyin, is worth less than 1⁄9400 of a US cent making it the "world's most worthless coin" that was still legal tender until 1 March 2020.

Official state figures put inflation as of the first half of 2011 at 3.6%, however accurate numbers are pinned far higher.

The second and current series, issued by the Central Bank of the Republic of Uzbekistan, was released in 1994 in denominations of 1, 3, 5, 10, 25, 50, and 100 sum.

On 2 September 2017, President of Uzbekistan Shavkat Mirziyoyev issued a decree "On priority measures of liberalizing foreign exchange policy".

Restrictions on the amount of foreign currencies individuals and companies could buy were also abolished on the same day.