What backs a stablecoin, and why B2B treasuries should care
"Stablecoin" is a claim, not a guarantee. The word describes a design goal — hold a 1:1 peg to a fiat currency — not a property that's automatically true. What makes the peg real is the reserve behind it, and reserves vary wildly between issuers.
The three reserve models in the market
- Fully-reserved fiat-backed. Cash and short-dated government securities held 1:1 against tokens in circulation, typically attested monthly by a third-party auditor. USDC and RLUSD follow this model.
- Fiat-backed with mixed reserves. A mix of cash, commercial paper, and other assets — historically the model with the most scrutiny (Tether/USDT has faced years of reserve-composition questions, though its disclosures have improved).
- Algorithmic / crypto-collateralized. No fiat reserve at all — the peg is maintained by code and market incentives. This category produced the highest-profile stablecoin collapse to date (Terra/UST, May 2022, ~$40B wiped out in days).
For B2B settlement, only the first category should be in scope. A payment rail is not the place to take on reserve-composition risk you didn't sign up for.
What to actually check
- Attestation frequency and auditor. Monthly attestations from a recognized accounting firm, published publicly — not "trust us."
- Reserve composition. Cash and short-term treasuries, not commercial paper, corporate bonds, or other stablecoins.
- Redemption rights. Can the reserve holder redeem 1:1 for fiat on demand, or only through a slow, gated process?
- Regulatory status. Is the issuer regulated as a money transmitter, e-money institution, or trust company in the jurisdictions it serves?
Why this matters more in B2B than consumer payments
A consumer holding a stablecoin for a few hours accepts some peg risk implicitly. A business settling six-figure supplier payments through a stablecoin leg cannot afford a de-peg event mid-transaction. Modality's settlement layer routes through fully-reserved, audited stablecoins (RLUSD, USDC, USDT) specifically because the settlement leg needs to be boring — it's infrastructure, not a trade.
FAQ
What backs USDC? Cash and short-duration U.S. Treasury securities, held in reserve accounts and attested monthly by an independent accounting firm.
Is USDT fully backed? Tether publishes quarterly attestations showing reserves including cash, treasuries, and other assets; reserve composition transparency has improved since 2021 but remains less granular than USDC's.
What happened to algorithmic stablecoins? The largest, TerraUSD (UST), lost its peg entirely in May 2022 because it had no fiat reserve — only a market-incentive mechanism that failed under stress, erasing roughly $40 billion in value within days.
Can a stablecoin lose its peg even if fully reserved? Briefly, yes — during extreme market stress or if redemption is paused (as USDC saw for hours during the March 2023 SVB crisis) — but full reserves mean the peg recovers once redemption resumes.
Does Modality issue its own stablecoin? No — Modality is a settlement layer that routes through existing audited stablecoins and licensed partners; it doesn't take on issuer risk itself.
Don't take a reserve claim on faith. Get a demo and see which assets actually move through your settlement path.