What a stablecoin actually is
A stablecoin is a blockchain-native token engineered to track a stable reference value — almost always the US dollar. Unlike Bitcoin or Ether, the whole point is that the price doesn't move. You hold one because you want a dollar that settles in seconds, on weekends, across borders, without a correspondent bank in the loop.
The category is now large enough to matter at a macro level. Total stablecoin supply crossed $320 billion in May 2026, with Tether's USDT around $189B and Circle's USDC near $77B. Two issuers control roughly four-fifths of the market — a concentration worth keeping in mind whenever someone calls this a decentralized technology.
How they hold the peg
There are three broad designs, and they are not equally safe.
Fiat-collateralized (USDT, USDC) hold reserves — cash and short-dated Treasuries — and promise redemption at par. The peg holds because arbitrageurs can mint and redeem against real assets. These see small, short depegs at worst.
Crypto-collateralized (DAI, and similar) lock volatile crypto as overcollateral, typically 150%+, with on-chain liquidation when collateral drops. More transparent, more capital-inefficient.
Algorithmic stablecoins try to hold the peg with code and a sister token instead of reserves. This is where the graveyard is. In May 2022, TerraUSD (UST) — then the third-largest stablecoin — entered a death spiral that erased roughly $60 billion. Once the market cap of the backing token LUNA fell below the UST it was supposed to redeem, the math stopped working and both went to near-zero. The lesson, in my view, has held: a peg defended only by confidence is not a peg.
Why it matters
Stablecoins are the most product-market-fit thing crypto has shipped. They're the dominant settlement asset on most exchanges, the unit of account across DeFi lending and DEX pools, and increasingly a real payments rail in economies with weak local currencies. The reserve model also makes large issuers meaningful buyers of US Treasuries — which is exactly why regulators stopped treating them as a niche.
For those of us building on regulated infrastructure, stablecoins are also the connective tissue to real-world asset tokenization: tokenized T-bills, money-market funds, and on-chain settlement all assume a credible on-chain dollar exists.
Key risks and tradeoffs
- Reserve quality and opacity. A token is only as good as what backs it. Attestations are not full audits, and "cash equivalents" can hide duration and counterparty risk.
- Centralization and freeze power. Major fiat-backed issuers can freeze addresses. That's a feature for compliance and a bug for censorship-resistance — you don't get both.
- Depeg contagion. Stablecoins are collateral everywhere in DeFi, so one wobble cascades through lending markets and liquidations.
- Regulatory fragmentation. The same token can be legal in one jurisdiction and delisted in another.
Current state (2026)
The regime changed fast on two fronts. In the US, the GENIUS Act was enacted in July 2025, creating the first federal framework for payment stablecoins: permitted issuers only, 1:1 backing in dollars or low-risk assets, and a choice of federal or state oversight (state-only capped at $10B issuance). Implementing rules from the OCC and others are landing through 2026.
In Europe, MiCA has been enforceable on stablecoins (which it calls e-money tokens and asset-referenced tokens) since mid-2025, with the transitional window closing July 1, 2026. The practical effect: MiCA-regulated venues have delisted non-compliant tokens, while issuers that obtained an EU e-money license — Circle's USDC among them — stayed listed. Working at a MiCA-compliant exchange in Liechtenstein, I'd say this is the single most consequential shift in the category: the question is no longer whether your stablecoin is liquid, but whether it's authorized in your jurisdiction.
The interesting fight ahead isn't USDT vs. USDC. It's whether yield-bearing and tokenized-deposit models can grow inside these new frameworks without re-creating the maturity-mismatch risk that the rules were written to prevent.
This is educational content, not financial advice. Stablecoins carry reserve, regulatory, and depeg risk; evaluate any specific token's backing and legal status before using it.