Short executive summary
Stablecoin market structure still looks concentrated at the top, but the layer below USDT and USDC is becoming harder for treasury and risk teams to ignore. As of the publication-day source refresh, 2026-05-26, DefiLlama showed total stablecoin market cap at $322.680B, with USDT dominance at 58.70%, USDT at $189.425B, and USDC at $76.487B. On the same date, CoinGecko showed a lower total stablecoin category market cap of about $318.1B, which is a useful reminder that stablecoin market data depends on methodology, coverage, and taxonomy.
The practical takeaway is not a safety ranking. This memo compares three narrower things: how market shares are moving, how issuer disclosure stacks differ, and what questions a DAO treasury or risk team should ask before making its own internal review. Market share is not issuer quality. Reserve-disclosure transparency is not a safety verdict.
Market snapshot with retrieval date
Fact — retrieved 2026-05-26. On DefiLlama, USDT and USDC together represented roughly 82.41% of the stablecoin market by the publication-day refresh calculation. That means the top two still dominate. But the 30-day movement below the top two is more interesting: USDT -0.13%, USDC -1.78%, USDS +6.93%, USD1 +9.74%, USDe +15.46%, PYUSD +4.68%, and RLUSD +11.46%.
Caveat. These market-share figures describe dashboard-observed supply and market-cap data at a specific retrieval timestamp. Dashboard values may drift after retrieval; figures reflect the stated retrieval timestamp. They are not a ranking of issuer quality, reserve safety, redemption resilience, legal status, or suitability for any treasury.
Interpretation. This does not prove a durable regime change. Thirty-day dashboard movement is not the same as long-term adoption, liquidity resilience, legal certainty, or redemption performance under stress. But it does show that the stablecoin market is broadening below the top two, and that market share needs to be monitored as a moving indicator, not treated as a static hierarchy.
Why market share alone is not enough
A large market share can indicate network effects, distribution, venue support, and user familiarity. It does not, by itself, answer reserve-quality or disclosure-quality questions. Market share is not issuer quality.
Treasury and risk teams usually need a second layer of analysis: what is the reserve model, how often reserves are disclosed, who verifies them, whether dashboards are live or report-based, and what caveats are attached by the issuer or third-party source.
There is also a taxonomy problem. CoinGecko’s category page separates stablecoins into subcategories such as fiat-backed, crypto-backed, synthetic dollar, and U.S. Treasury-backed stablecoins. Ethena’s own documentation states that USDe is not the same as fiat stablecoins like USDC or USDT; it is a synthetic dollar backed by crypto assets and corresponding short futures positions. That means putting USDe, USDT, USDC, PYUSD, RLUSD, USD1, and Treasury/RWA-like instruments into one broad “stablecoin” list may be useful for market monitoring, but it is not sufficient for due diligence. Fiat-backed tokens, synthetic dollars, and Treasury/RWA-like instruments require different due-diligence paths.
Reserve disclosure matrix
| Issuer / token | Category / due-diligence path | Reserve model | Disclosure cadence | Third-party verification | Live dashboard or formal report | Main caveat | Source references / retrieval date |
|---|---|---|---|---|---|---|---|
| Circle / USDC | Fiat-backed issuer reserve-disclosure path; review issuer reserve page, fund structure, third-party assurance, and fund caveats. | Majority of reserve invested in Circle Reserve Fund; fund scope includes short-dated U.S. Treasuries, cash, and overnight repo per BlackRock materials. | Weekly reserve disclosure; monthly assurance. | Monthly third-party assurance as described by Circle. | Circle transparency page plus BlackRock fund visibility. | Disclosure quality does not remove custody, market, operational, or redemption risks; BlackRock caveat says fund is not FDIC-insured and does not guarantee $1 NAV. | Circle Transparency, Circle USDC page, BlackRock Circle Reserve Fund page and prospectus; retrieved 2026-05-26; Circle reserves page as of May 21, 2026; BlackRock fund data as of 22-May-2026; prospectus filed 2024-08-28. |
| Tether / USDT | Fiat-backed / multi-asset reserve attestation path; review transparency page, attestation announcement, reserve mix, and audit-status wording. | Reserve mix includes large U.S. Treasury exposure, plus other assets such as gold and bitcoin per Q1 2026 announcement. | Circulation metrics typically refreshed daily; reserve disclosure through attestations. | BDO-prepared attestation for Q1 2026. | Transparency page plus attestation announcement. | Attestation is not the same as a completed full audit; official announcement says audit process formally commenced. | Tether Transparency live page and Q1 2026 attestation announcement; retrieved 2026-05-26; announcement dated 2026-05-01, with figures as of March 31, 2026. |
| Ripple / RLUSD | Fiat-backed issuer / monthly CPA attestation path; review reserve balances, custodian context, and reporting history. | U.S. dollar deposits, U.S. Treasuries, and cash equivalents; segregated reserve accounts; BNY custodian context. | Monthly CPA attestations. | CPA attestation. | Transparency page and formal reports. | Public disclosure exists, but long stress-history and redemption resilience are not proven by this source set. | Ripple RLUSD product page and RLUSD transparency page; retrieved 2026-05-26; transparency balances as of 05/21/2026. |
| USD1 | Fiat-backed / cash and government money-market-fund disclosure path; review formal attestations separately from live PoR dashboard. | Cash, U.S. government money market funds, and other cash equivalents; BitGo issuance/custody context. | Monthly attestations; live proof-of-reserves design. | AICPA-based monthly attestation framework as described by issuer docs. | Chainlink-based PoR dashboard plus formal monthly reports. | Live PoR dashboard can be a monitoring signal, but it is not a substitute for formal monthly attestation reports; issuer docs caveat that dashboard data accuracy is not guaranteed. | USD1 “What is USD1?”, USD1 Attestation Reports, USD1 Proof of Reserves docs; retrieved 2026-05-26; docs dated 2026-03-03 / 2026-03-04; attestation page showed “Last updated 1 day ago”; PoR page showed “Last updated 29 days ago”. |
| Paxos / PYUSD | Fiat-backed issuer / monthly reserve-report path; review reserve assets and latest report date. | U.S. dollar deposits, U.S. Treasuries, and cash equivalents. | Monthly reserve reports / attestations. | Monthly reporting / attestation stack. | Formal transparency reports. | Clear reserve model does not prove liquidity depth, usage depth, or fit for every treasury policy. | Paxos PYUSD product page and PYUSD Transparency Reports; retrieved 2026-05-26; live product/reporting pages with 2026 reports visible. |
| Ethena / USDe | Synthetic-dollar due-diligence path; do not review as fiat-backed reserve model. | Synthetic dollar backed with crypto assets and short futures positions. | Monthly custodian attestations. | Custodian attestations. | Protocol docs, custodian attestations, reserve-fund documentation. | Not a fiat-backed stablecoin; it requires a different due-diligence path from fiat-backed reserve models. | Ethena Overview, Custodian Attestations, Reserve Fund docs; retrieved 2026-05-26; custodian-attestation page showed “Last updated 23 hours ago,” with 2026 attestation entries visible through March 2026; reserve-fund page showed “Last updated 7 months ago”. |
Author synthesis. The strongest comparison is not “who is safe.” It is whether the issuer’s disclosure stack gives a treasury team enough dated, repeatable, independently checked information to support its own internal review process. Transparency is useful for review, but transparency is not safety.
Chain concentration note
Stablecoin exposure is also chain-specific. DefiLlama’s chain view, retrieved 2026-05-26, showed Ethereum at $162.945B, Tron at $90.739B, Solana at $14.701B, Hyperliquid L1 at $6.808B, Base at $4.710B, and XRPL at $725.97M. The dominant issuer also varied sharply by chain in the source snapshot.
This proves supply concentration by chain. It does not prove chain safety, venue liquidity, bridge safety, or operational suitability. Dashboard values may drift after retrieval; figures reflect the stated retrieval timestamp.
Treasury/risk questions to ask
- Which taxonomy does the asset belong to: fiat-backed, synthetic dollar, crypto-backed, U.S. Treasury-backed, Treasury/RWA-like, or another disclosed model?
- What assets are claimed to back the token, and where are they held?
- How frequently are reserve disclosures updated?
- Is there independent verification, and is it an attestation, assurance report, audit, custodian attestation, or something else?
- Does the issuer offer a live dashboard, a formal report, or both?
- What does the issuer itself say the dashboard does not prove?
- Is a dashboard being treated as a monitoring signal, or incorrectly treated as a formal attestation?
- Is an attestation being treated as a useful verification artifact, or incorrectly treated as a completed full audit?
- How concentrated is supply by chain?
- How would the team monitor changes in market share, reserve reports, and chain concentration over time?
What this does NOT prove
This memo does not rank stablecoins by safety. It does not rank issuers by quality. It does not establish legal, tax, accounting, or compliance conclusions. It does not prove issuer solvency under all stress scenarios. It does not prove redemption performance during market stress. It does not provide instructions for actions with assets. It does not prove that live dashboards are formal attestations. It does not prove that attestations are completed full audits. It does not prove Treasury Desk demand, customer traction, WTP, PMF, production adoption, or legal readiness.
Treasury Desk can support a repeatable public-source stablecoin watch: dated market snapshots, issuer disclosure tracking, chain-concentration notes, and review checklists. The output is monitoring and decision-support, not investment, legal, tax, accounting, compliance, or action guidance with assets.
Final caveat
This memo is for public-source monitoring and educational discussion only. Market share, reserve-disclosure cadence, attestations, assurance reports, live dashboards, and issuer transparency materials should not be interpreted as a ranking of stablecoin safety, issuer quality, treasury suitability, redemption resilience, or legal status. Dashboard values may change after retrieval and reflect only the stated retrieval timestamp. Live proof-of-reserves dashboards are monitoring signals, not substitutes for formal reports or attestations. Different asset categories, including fiat-backed tokens, synthetic dollars, and Treasury/RWA-like instruments, require different due-diligence paths.