A stablecoin is a cryptocurrency built to hold a fixed value, almost always $1, instead of floating with the market the way Bitcoin or Ether does. It does that by holding real dollar-denominated assets in reserve, over-collateralizing with other crypto, or running an algorithm that expands and contracts the token's supply, and which method it uses determines how safe it actually is. More than $320 billion sits in stablecoins as of 2026, and the difference between the safer kind and the kind that has gone to zero is not subtle once you understand what's actually backing the number in your wallet.
How Do Stablecoins Actually Stay at $1?
A stablecoin stays near $1 through one of three mechanisms, and they are not interchangeable in terms of risk:
- Fiat-backed. Each token is backed roughly 1:1 by cash and cash equivalents, usually short-term U.S. Treasuries, held by the issuer. The two largest examples, Tether's USDT and Circle's USDC, work this way. In the first quarter of 2026 alone, USDT's supply contracted by roughly $3 billion while USDC added about $2 billion to reach $78 billion, real money moving between issuers based on which one the market trusted more that quarter.
- Crypto-backed. Instead of cash, the token is backed by other cryptocurrency, typically locked up at more than the value of the stablecoin issued against it (often 150% or more) to absorb price swings in the collateral. If the collateral's value falls too far, the system automatically liquidates it to protect the peg.
- Algorithmic. No real reserves at all. The peg is maintained purely through code and market incentives designed to expand or contract supply automatically. This is the riskiest structure by a wide margin, and it has a well-documented failure case, covered below.
What Happens When a Stablecoin Breaks the Peg?
Breaking the peg means the token's market price moves away from its $1 target, and what happens next depends entirely on what's actually standing behind it. Two real, well-documented events from the past few years show just how differently that can go.
TerraUSD (UST), May 2022: total collapse. UST was an algorithmic stablecoin with no cash or asset reserves behind it, only a paired token (LUNA) and a market-incentive mechanism. On May 8, 2022, a large sell-off of roughly $285 million in UST triggered a depeg to $0.98. Within two days it had fallen to $0.67, and the death spiral that followed erased more than $40 billion in combined UST and LUNA market value within about three days, with total losses across the wider crypto market estimated above $400 billion. There was no reserve to fall back on, because there wasn't one to begin with. Holders who didn't exit in the first hours lost nearly everything.
USDC, March 2023: a real depeg that recovered. USDC is fiat-backed, and Circle disclosed that $3.3 billion of the cash reserves behind it were sitting at Silicon Valley Bank when regulators closed it on March 9, 2023. USDC dropped to a low of $0.87 within two days on that news. But because the underlying reserves were real dollars, not code, USDC recovered to roughly $1 within about three days once the FDIC backstopped SVB's depositors and Circle confirmed the reserves were intact. The difference between a token that recovers and one that goes to zero is whether there was ever a real asset behind it in the first place.
Does the GENIUS Act Make Stablecoins Safe Now?
No, not automatically, and not yet in full. The GENIUS Act, signed into law in July 2025, is the first federal law creating a real regulatory framework for fiat-backed stablecoins in the U.S. It requires payment stablecoins to be backed 1:1 by cash or short-term Treasuries, and it restricts who can legally issue one to banks, approved nonbanks, and qualified state issuers. That's a genuine improvement over the unregulated environment that let something like UST exist in the first place. But the law's implementing regulations weren't due until July 2026, and full enforcement doesn't kick in until no later than January 2027, so a stablecoin you hold today may not yet be operating under the finished version of these rules. Treat the law as a real, meaningful improvement in progress, not a guarantee that's already fully in force.
The Real Risks Stablecoins Carry, Even the "Safe" Kind
- No FDIC or SIPC insurance, ever. A stablecoin is not a bank deposit or a brokerage balance, regardless of how "cash-backed" its marketing sounds. If the issuer fails or the reserves turn out to be short, there's no government insurance program standing behind your balance the way there is for a checking account under $250,000.
- Reserve quality is not one-size-fits-all. "Backed by reserves" can mean fully audited cash and short-term Treasuries, or it can mean a mix of assets with less transparency and only periodic attestations rather than a full independent audit. Those are very different risk profiles wearing the same label.
- Issuers can freeze tokens. Major fiat-backed issuers have the technical and legal ability to freeze balances at specific wallet addresses, typically in response to law enforcement requests. That's a real trade-off against the "unstoppable digital cash" framing you'll see in crypto marketing, worth knowing before you rely on one.
- Smart contract and platform risk stack on top. Holding a stablecoin in a personal wallet is one risk profile. Depositing it into a DeFi lending or yield protocol adds a second layer of risk, the protocol's own code and solvency, on top of the stablecoin's own backing.
- Regulatory risk is still live. Rules are actively being finalized in the U.S. and elsewhere. What's legal, insured, or required of an issuer today can change by the time enforcement is fully in place.
What to Check Before You Hold Any Stablecoin
If you're using a stablecoin for anything beyond a brief pass-through in a trade, a few questions are worth answering first: Does the issuer publish regular reserve attestations, and how often? Is the backing cash and short-term Treasuries, or something more complex? Is the issuer a bank or approved nonbank under the GENIUS Act framework, or operating outside it? And are you simply holding it, or depositing it into a protocol that adds its own layer of smart contract risk on top? None of this is a reason to avoid stablecoins outright. It's the same due diligence you'd apply to any place you're parking real money, applied to an asset class that doesn't come with the safety net a bank account does.
If you're holding crypto more broadly, our breakdown of what happens to your crypto if the exchange goes bankrupt covers a related risk that applies whether you're holding a stablecoin or anything else on an exchange. And if you're earning yield on a stablecoin through staking or a lending protocol, the tax treatment works the same way we broke down in how crypto staking rewards are taxed, taxable as income the moment you receive it, regardless of what the token's price does afterward.
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Spicy Investing