Stablecoin depeg risks are easy to underestimate, because stablecoins feel like digital dollars. A stablecoin is designed to hold a target value, usually one US dollar, but that peg is a market outcome, not a guarantee. When confidence breaks, a stablecoin can trade well below its target for hours, days, or permanently, and holders who assumed they owned something as safe as cash discover they owned something riskier. Understanding how pegs work, and how they break, is essential before holding any meaningful amount.

A stablecoin's price stays near one dollar through redemption and arbitrage. For fiat-backed coins, holders can redeem tokens with the issuer for a dollar's worth of reserves, so if the market price dips to ninety-nine cents, traders buy cheap tokens and redeem them at full value, pushing the price back up. For crypto-collateralised coins, smart contracts and over-collateralisation play a similar role, with liquidations defending the peg. The system works as long as redemption is fast, reserves are real and accessible, and markets stay liquid enough for arbitrage to function.

Depegs happen when one of those supports fails. The most common cause is doubt about reserves: if holders suspect the issuer does not hold enough safe assets, they sell first and ask questions later, overwhelming the arbitrage mechanism. Reserves can also become stuck, for example when a banking partner fails and reserve deposits are temporarily inaccessible, as happened with a major stablecoin in March 2023 when part of its reserves sat at a collapsing bank. Crypto-collateralised coins face a different failure: if the collateral crashes faster than liquidations can handle, the backing itself shrinks below the issued supply.

Analysts generally distinguish three kinds of depeg. A venue depeg affects one exchange or market where liquidity dried up, and usually recovers within hours as arbitrageurs move in. A confidence depeg affects the whole market when reserves or redemption are doubted, and recovers only if reserves prove intact and redemptions resume normally. A terminal depeg happens when the backing itself fails, as with algorithmic designs whose value spiral cannot be stopped, and does not recover. Knowing which type you are watching matters, because the right response differs: a venue depeg may be a buying opportunity for experts, while a terminal depeg rewards fast exits.

Algorithmic stablecoins deserve special caution. Instead of holding cash reserves, they maintain the peg through supply algorithms and a sister token, a design that works in calm markets but can enter a reflexive death spiral when the sister token falls, since each round of stabilisation dilutes it further. The most famous collapse of this type erased tens of billions in value within a week in May 2022, and it remains the clearest lesson in the space: a peg maintained by confidence alone is only as strong as that confidence, and confidence evaporates fastest exactly when it is needed most.

Before holding a meaningful amount of any stablecoin, run through a short checklist. What backs it: cash and short-term government securities score far better than opaque assets or algorithms. How often are reserves reported, and by whom: frequent, independent attestations beat vague promises. Can you actually redeem, or is redemption limited to large institutions with minimum sizes and delays? Is the backing concentrated in one bank, one custodian, or one strategy? And how deep is exchange liquidity, so you can exit without huge slippage in a stress event?

Practical habits reduce depeg risk further. Diversify across issuers for large balances rather than holding everything in one coin, keep only amounts you need for trading or payments in stablecoins rather than treating them as savings, and watch early warning signs such as redemption delays, late reserve reports, growing pool imbalances on decentralised exchanges, and price differences across venues. Stablecoins are genuinely useful tools for trading and transfers, but they are not bank deposits, they are generally not covered by deposit insurance for token holders, and treating them as risk-free cash is the mistake that turns a manageable depeg into a serious loss. This article is educational only and not financial advice.