After several fluctuations in earlier years, the price of Tether or USDT since 2020 achieved the stability against the U.S. dollar that it was designed to reach. In 2021, Tether ranks as one of the biggest cryptocurrencies in the world and is regarded as the most well-known "stablecoin", or cryptocurrency that is connected to the price development of another, real-world asset. As Tether's USDT code suggest, the token is, in this case, connected to the U.S. dollar. This effectively means that a single Tether will nearly always be worth one single U.S. dollar. This relative stability, unlike the price development of, say, Ripple (XRP), is what defines a stablecoin and is especially important for decentralized lending and borrowing. This particular segment made up roughly half of the overall value locked in Decentralized Finance or DeFi.

Prices for USTUSD Tether / US Dollar including live quotes, historical charts and news. USTUSD Tether / US Dollar was last updated by Trading Economics this September 7 of 2025.

The price of Terra's algorithmic stablecoin UST collapsed severely in May 2022, declining by over 95 percent in the span of a few days. This came as a surprise to many, given the promise the stablecoin held. Simply put, Terra claimed to have created a smart contract system that can keep the price of its (stable)coin more stable than that of other digital currencies. It would do so by using an algorithm that automatically sacrifices ("burns") LUNA tokens - the cryptocurrency of the same Terra blockchain - in order to create new UST coins. This is a big deal for Decentralized Finance or DeFi, as some of the most valued segments in DeFi rely on price stability in order to function. The concept of an algorithm that automatically adds or removes supply, irrespective of sentiment, is different from other popular stablecoins such as Tether (USDT), which are either backed by the fiat currencies like the U.S. dollar or external crypto assets. As of May 19, 2025, the price of UST is approximately 12.55.