What Are Stablecoins and How Do They Work?

Most cryptocurrency prices swing wildly — a coin can gain or lose tens of percent in a single day. That volatility makes crypto impractical for everyday spending or short-term saving. This is where stablecoins come in: a middle ground between the crypto world and the steadiness of traditional money.

What Are Stablecoins?

A stablecoin is a digital currency designed to hold its value as close as possible to a fixed reference point — usually one US dollar per unit. Instead of riding the ups and downs of the market, you get a digital asset that keeps roughly the same value while still moving at crypto speed: transfers in minutes, 24/7, across borders, at low cost.

The best-known examples are USDT (Tether) and USDC, both pegged to the dollar.

Why Do We Even Need Them?

• Shelter from volatility: Convert your balance into a stablecoin to sidestep market swings without leaving crypto altogether.
• Fast transfers: Send value across countries in minutes instead of days.

The Three Types of Stablecoins

Not all stablecoins are built the same way. What actually backs their price varies a lot from one type to another — and that difference is the key to understanding the risk.

1. Fiat-Backed

The issuer holds a real reserve of dollars (or short-term treasury bills) in bank accounts, so that every coin in circulation is matched by a dollar held in reserve. Deposit a dollar, a coin is minted; redeem it, the coin is burned. This is the simplest and most common type — think USDT and USDC.

• Strength: Straightforward and easy to understand, with tangible backing.
• Weakness: Depends on trust in the issuer and how transparent (and regularly audited) its reserves are.

2. Crypto-Backed

Here, the backing is other cryptocurrencies (like Ethereum) locked in smart contracts. Because that collateral is itself volatile, these systems require over-collateralization: you might lock up around $150 worth of crypto to mint $100 worth of stablecoin, giving the system a cushion if the market drops — the exact ratio varies by protocol and by which asset you post. DAI is the best-known example, though since MakerDAO rebranded to Sky its successor token USDS has overtaken it, at roughly $9.8 billion against DAI's $4.6 billion as of August 2026.

• Strength: More decentralized, with everything visible on-chain.
• Weakness: More complex, and your collateral can be automatically liquidated if the market falls sharply.

3. Algorithmic

These don't rely on a real reserve at all — instead, algorithms and smart contracts automatically expand or shrink the supply to push the price back toward a dollar. It sounds elegant on paper, but in practice it's the most fragile design, and some have collapsed completely, as we'll see below.

How Is the Dollar "Peg" Maintained?

The peg is the promise that one coin equals one dollar. It's maintained through two main mechanisms:

1. Mint and burn: The issuer creates new coins when money comes in and destroys them on redemption, keeping supply matched to demand.
2. Arbitrage: If the price dips to $0.98, traders buy the "discounted" coin so they can redeem it for a full dollar — that buying pressure pushes the price back up. The reverse happens if the price rises above a dollar.

These mechanisms work well as long as trust holds and reserves stay sufficient and liquid. When trust breaks down, the whole equation can break down with it.

De-Peg Risk — Let's Be Honest About It

A de-peg happens when a coin loses its footing and drifts away from the dollar, up or down. Sometimes it's a brief, minutes-long wobble; sometimes it's permanent and devastating.

The main causes:

• Insufficient or opaque reserves in fiat-backed coins.
• Market crashes that liquidate the collateral behind crypto-backed coins.
• A collective loss of confidence that sends everyone rushing to redeem at once — not unlike a bank run.
• Flaws in algorithmic design: the most infamous case is the collapse of UST (Terra) in May 2022, which lost its dollar peg and collapsed. The Federal Reserve's note The stable in stablecoins records that the collapse pushed the market capitalisation of uncollateralised stablecoins back to 2021 levels, and spilled over to smaller stablecoins and, to a lesser extent, to the larger ones, Tether in particular. This isn't a hypothetical — it's a real warning.

How to Use Stablecoins Safely

• Stick to major, established coins with transparent reserves and deep liquidity.
• Know the type: fiat-backed, crypto-backed, or algorithmic?
• Double-check the network: make sure you're sending on the right network (like TRC20 or BEP20) to avoid losing funds.
• Diversify — don't rely on a single issuer if you're holding significant amounts.

The Bottom Line

Stablecoins are a practical tool that combines the stability of the dollar's value with the speed of the blockchain. But "stable" doesn't mean "risk-free": understand the type of coin you're using, what backs it, and the limits of its stability, so you can make an informed decision.

Frequently asked questions

How do stablecoins work?

A company issues a token and promises to redeem it for one dollar, holding reserves that back that promise. The token itself moves on a blockchain like any other, so it settles in minutes and needs no bank. The dollar value comes from the redemption promise and from traders who buy below one dollar and sell above it, not from anything about the token.

Is holding a stablecoin the same as holding dollars in a bank?

No, and the difference matters most when something goes wrong. A bank deposit in many countries carries government-backed insurance up to a limit — in the United States the FDIC insures deposits to at least $250,000 at each insured bank, and lists crypto assets among the products it does not cover. A stablecoin carries a company's promise to redeem, backed by reserves it holds. Both may work fine for years. Only one has a public guarantor if the issuer fails.

Do stablecoins pay interest just for holding them?

Not by themselves. A stablecoin sitting in your wallet earns nothing, and the issuer keeps whatever its reserves earn. Yields advertised on stablecoins come from lending them out or depositing them in a platform, which introduces the risk of that platform rather than of the coin. Rates presented as risk-free are describing someone else's risk.

Who guarantees that one stablecoin is worth one dollar?

Nobody, in the sense of a legal guarantee. The peg is maintained by the issuer redeeming coins for dollars and by arbitrage traders buying below and selling above. Both mechanisms depend on the issuer holding real reserves and honouring redemptions, which is why reserve reporting is the thing worth reading about a stablecoin.

Are stablecoins legal?

That depends entirely on where you live: rules differ sharply by country, and some restrict or ban them outright. In the European Union, the Markets in Crypto-Assets Regulation brings the issuing and trading of stablecoins — asset-referenced tokens and e-money tokens, in its wording — under one rulebook. It entered into force in June 2023, but issuers of those two token types only came under it on 30 June 2024, the date the European Banking Authority gives in its guidance on asset-referenced and e-money tokens under MiCA. Because this changes quickly, check what applies where you live rather than relying on any general statement, including this one.

Is a stablecoin the same as a central bank digital currency?

No. A stablecoin is issued by a private company and backed by reserves it chooses to hold; a central bank digital currency would be issued by the state and be a direct claim on it, the way physical cash is. They can look similar in a wallet and are entirely different in who stands behind them.