USDT is issued by Tether Holdings Limited, a British Virgin Islands-registered company that operates principally out of El Salvador. With supply near $190B in early 2026, USDT is the largest stablecoin by float — roughly 60% of total stablecoin supply globally. Reserves span U.S. Treasuries, cash and cash equivalents, secured loans, gold, and Bitcoin. Attestations are published quarterly by BDO Italy. This article walks through how Tether's reserves are actually composed, how the attestation regime works, the regulatory history that shapes how Tether operates today, and where USDT sits in payments and DeFi flows.
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Tether is the most controversial of the major stablecoin issuers — and also the most used. Understanding what's actually in the reserves, what the attestations cover, and what the historical CFTC and NYAG settlements addressed is the prerequisite for any honest assessment of USDT risk. The goal here is to lay out the facts as published, sourced to primary documents.
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Tether Holdings Limited is the BVI-registered entity that issues USDT. Operations are run from El Salvador since 2024, where Tether holds a Digital Asset Service Provider license. The original Tether token launched on Bitcoin's Omni layer in 2014; it has since expanded to 14+ chains including Ethereum, TRON, Solana, Avalanche, Polygon, Arbitrum, and Toncoin. TRON carries the largest USDT supply by chain — approximately $86B — driven by emerging-market remittance flows where TRON's low transaction fees dominate retail use.
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Tether is owned by iFinex, the parent of Bitfinex exchange. The shared ownership is part of Tether's regulatory history; the 2021 NYAG settlement explicitly addressed the relationship between Tether reserves and Bitfinex liabilities. The NYAG settlement document is the primary source on what was agreed and disclosed.
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Tether mints USDT on request from approved counterparties — institutional clients onboarded through Tether's compliance process. The flow mirrors other fiat-backed issuers: the counterparty wires funds to a Tether-controlled account, Tether credits the reserve, and an equivalent amount of USDT is minted to the counterparty's wallet. Redemption requires a $100,000 minimum and is processed through the same counterparty channel.
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The effective retail experience is that exchanges and OTC desks act as the bridge between bank wires and onchain USDT. Coinbase, Bitfinex, Kraken, and large OTC desks hold Tether-mint accounts; retail users transact in USDT through these venues without touching Tether directly.
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USDT mints and burns are visible onchain — every issuance and every redemption shows up as a treasury contract transaction on the source chain. Santiment dashboards and the Tether transparency page both track these flows in near real time, which is one of the most frequently watched market signals: large mints often correlate with risk-on positioning and large burns with risk-off.
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Tether's reserve composition is published quarterly on tether.to/en/transparency alongside the BDO attestation. The Q4 2025 breakdown (published early 2026) shows roughly:

"Excess reserves" — the buffer above 1:1 backing — sit in the more volatile categories (BTC, gold, equity stakes) and are reported separately. Tether typically reports excess reserves of $5–10B above outstanding USDT supply, which functions as a loss-absorbing layer above the per-token reserve assertion.
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Tether publishes quarterly reserve attestations from BDO Italy. The attestations are agreed-upon-procedures reports — point-in-time confirmations that, on the reporting date, reserves matched supply per the asserted categories. They are not full GAAS audits. Tether has stated intent to pursue a full audit and engaged multiple firms over the years; as of early 2026, the attestation regime continues, with a Big Four engagement still pending.
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The attestation cadence matters for context against Circle and Paxos, both of which publish monthly Deloitte and Withum attestations respectively. Quarterly is less frequent but still meaningful — the disclosed reserves at the snapshot dates are independently reviewed.
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Historical disclosure issues have been settled: the 2021 CFTC settlement ($41M) addressed misrepresentations about USDT reserve backing during 2016–2018. The NYAG settlement ($18.5M) addressed similar disclosure issues and the Bitfinex/Tether intercompany lending. Both settlements predate the current attestation and reserve-composition regime; both are part of Tether's record and are referenced in any complete description of the issuer.
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USDT runs on 14+ chains including Ethereum, TRON, Solana, Avalanche, Polygon, Arbitrum, Optimism, BNB Chain, EOS, Algorand, Tezos, Toncoin, and Liquid (Bitcoin sidechain). Distribution is heavily skewed:

The 1:1 peg holds across chains because Tether allows authorized counterparties to swap USDT between supported chains 1:1 — burn on chain A, mint on chain B. This is the cross-chain mechanism most relevant for liquidity providers; retail users typically use bridges or aggregators to move USDT between chains. Cross-chain stablecoin swap infrastructure covers the routing options.
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Tether has not pursued U.S. or EU regulatory registration. The token is not licensed under MiCA in the EU; major MiCA-regulated EU exchanges delisted USDT for EU residents in late 2024 as a result. In the U.S., Tether operates as a non-registered offshore issuer; redemption is available only to non-U.S. persons through approved counterparties. The proposed U.S. GENIUS Act would require federal or state-licensed issuance for any payment stablecoin used in U.S. commerce — a structural change Tether would need to address to serve U.S. customers directly.
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El Salvador's 2024 Digital Asset Service Provider regime is the primary regulatory framework Tether operates under. The license requires reserve attestations, AML compliance, and supervisory reporting, but is not equivalent in scope to NY DFS or MiCA structures.
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USDT is the dominant stablecoin for cross-border remittances and emerging-market settlement. The TRON USDT footprint in particular handles a large share of retail dollar-equivalent flows in Argentina, Turkey, Vietnam, Nigeria, and other markets where local-currency volatility makes a USD-equivalent token operationally useful. In DeFi, USDT is widely supported but typically secondary to USDC in lending and isolated-pool TVL — a pattern shaped by perceived reserve-transparency differences.
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For institutional treasury programs operating in U.S. or EU regulated environments, USDC and PYUSD are the typical operating defaults; USDT is often present in cross-border or emerging-market settlement legs but not as the primary operating account. USD-to-USDT conversion covers the practical onboarding flow.
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Beyond USDT, Tether issues several adjacent tokens that share the issuer infrastructure:

The non-USD-denominated Tether stablecoins are operationally separate from USDT — different reserve pools, different attestation scope — but share the broader Tether issuance infrastructure and counterparty network. Most volume sits in USDT itself; the alternatives serve specific currency-exposure use cases.
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Tether also operates Tether Investments, a corporate venture arm that holds equity stakes in Bitcoin mining (Bitfarms, Northern Data), AI infrastructure (Holepunch, Northern Data AI), and other portfolio companies. These investments are funded from excess reserves and protocol revenue rather than the per-token reserve pool. Tether's news page publishes investment updates regularly.
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Eco routes USDT alongside USDC, PYUSD, USDS, and USDe across 15+ supported chains. The orchestration layer is issuer-agnostic — a treasury team holding USDT on TRON for emerging-market settlement and USDC on Base for U.S. payments can integrate Eco once and route both. For USDT specifically, Eco selects between LayerZero's OFT, Stargate, and authorized-counterparty 1:1 mint/burn routes depending on the chain pair and size.
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USDT is backed primarily by U.S. Treasuries (~80%), cash and cash equivalents, gold (~5%), Bitcoin (~3%), secured loans (~5%), and other investments. The full breakdown is published quarterly with a BDO attestation. See USD-backed stablecoin infrastructure for the broader category.
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Tether publishes quarterly agreed-upon-procedures attestations from BDO Italy. These are point-in-time reserve confirmations rather than full GAAS audits. Tether has indicated it is working toward a full audit; as of early 2026, the quarterly attestation regime continues.
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The 2021 CFTC settlement ($41M) addressed misrepresentations about USDT reserve backing during 2016–2018, when reserves did not consistently match the public 1:1 USD assertion. The settlement predates the current attestation and reserve-composition regime; current quarterly disclosures publish full category breakdowns.
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TRON's transfer fees (typically under $1) are dramatically lower than Ethereum's, which makes TRON the operationally cheaper venue for retail and remittance flows. Roughly $86B of USDT supply sits on TRON, driven by emerging-market USD-equivalent demand where transaction-cost sensitivity is highest.
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Tether has not registered USDT under MiCA. Major MiCA-regulated EU exchanges delisted USDT for EU residents in late 2024. EU users typically transact in MiCA-compliant alternatives (USDC, EURC) on regulated venues; USDT remains accessible through non-EU venues.
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