Stablecoins have become one of the most important building blocks in digital-asset markets. They sit at the centre of trading, liquidity and payments, and in some periods see higher transaction volumes than Bitcoin or Ethereum. But what exactly are stablecoins, and how stable are they in practice?
A stablecoin is a digital asset designed to maintain a stable value relative to another asset. In simple terms, it is pegged to something else, with the aim of keeping its price consistent over time. While many people assume stablecoins are always pegged to the US dollar, there are several different models in use today, each with its own risk profile.
The most widely used stablecoins are fiat-backed, typically pegged 1:1 to the US dollar. Tether (USDT), for example, is designed so that one token represents one US dollar in value. These stablecoins aim to maintain stability through reserves held by the issuer.
Stablecoins can also be crypto-collateralised, where their value is backed by other digital assets such as Ethereum or Bitcoin, often held in excess to absorb price volatility. Others are commodity-backed, with their value linked to assets like gold or silver.
Finally, there are algorithmic or non-collateralised stablecoins. These are not backed by reserves such as cash, bonds or crypto assets. Instead, they rely on mechanisms that expand or contract supply – issuing or burning tokens – in an attempt to keep the price close to a target value, usually £1 or $1. These designs depend heavily on market confidence, which makes them more fragile during periods of stress.
The goal across all stablecoin models is the same: to maintain a consistent relationship with the underlying reference asset, typically on a 1:1 basis. Achieving that stability reliably, however, is the real challenge.
Why are stablecoins so important?
Stablecoins matter for two main reasons. First, they allow users to store value and move capital within the crypto ecosystem without being exposed to the price volatility of assets like Bitcoin. In that sense, they act as a stabilising layer within highly volatile markets.
Second, stablecoins enable faster and lower-cost payments on blockchain networks. By removing intermediaries and settlement delays, they have the potential to challenge slower and more expensive legacy systems such as SWIFT, particularly for cross-border transactions.
Why are so many stablecoins pegged to the US dollar?
Although there is a growing variety of stablecoins, the majority remain pegged to the US dollar. A key reason is the 2025 GENIUS Act, which introduced a clear regulatory framework for payment stablecoins in the United States.
The legislation incentivises USD-pegged stablecoins by structuring reserve, disclosure and licensing requirements around the US dollar and US financial instruments. In practice, this makes USD pegs the simplest, safest and most scalable option for regulated issuers.
Under the Act, issuers must hold high-quality, liquid reserves equal to the value of stablecoins in circulation, alongside regular disclosures and regulatory oversight. By limiting issuance to approved entities and tightening reserve and governance standards, the framework aims to reduce structural risk in stablecoin markets – improving transparency, comparability and confidence in assets that play a central role in digital-asset liquidity.
Over time, this landscape may evolve. While central banks are developing their own digital currencies (CBDCs), these are distinct from privately issued stablecoins. Their emergence may reshape how digital money is used globally, but dollar-denominated stablecoins are likely to remain dominant in crypto markets for the foreseeable future.
Are stablecoins truly stable?
Not all stablecoins carry the same level of risk. Fiat-backed, fully collateralised stablecoins should, in theory, maintain their peg under normal market conditions. Others, particularly algorithmic models, rely on confidence and market behaviour, which can break down quickly during periods of stress.
Regulation will play an increasing role in separating resilient designs from weaker ones. Higher reporting standards and stronger governance should improve transparency, but they may also change how closely some stablecoins can maintain a strict 1:1 relationship over time.
Finding the right balance is critical. Too much rigidity could limit innovation, while too much flexibility may expose users to unnecessary risk. What matters most is principled regulation — frameworks that improve trust and stability without undermining the utility that makes stablecoins valuable in the first place.
Stablecoins are now central to modern digital-asset markets. They are not speculative assets in the way cryptocurrencies are, but essential liquidity and settlement tools. Understanding how they work — and where the risks lie — is key to using them effectively.