What a stablecoin is, mechanically
A fiat-backed stablecoin is a token whose issuer promises to redeem it one-for-one for dollars. The issuer holds reserves — mostly short-term US Treasury bills and cash — and mints tokens when institutions deposit dollars, burns them when institutions redeem. Everyone else buys and sells the tokens on the secondary market, where they trade within a fraction of a cent of $1 because arbitrageurs can always redeem or mint at par.
The token itself is an entry on a blockchain. That is what makes it the "internet dollar": it settles in seconds to minutes, around the clock, to any address in the world, with no bank in the path. The two that matter are USDT (Tether) and USDC (Circle); together they are the overwhelming majority of the market, and USDT alone circulates well over a hundred billion dollars.
USDT vs USDC: the differences that matter
| USDT (Tether) | USDC (Circle) | |
|---|---|---|
| Issuer | Tether, El Salvador-domiciled since 2025 | Circle, US-based, publicly listed since 2025 |
| Reserve reporting | Quarterly attestations; reserves mostly T-bills plus some Bitcoin, gold and other assets | Monthly attestations; reserves in T-bills, repo and cash at regulated banks |
| Where it dominates | Emerging markets, P2P, TRON; the deepest liquidity in Asia and Latin America | US and EU institutions, DeFi on Ethereum and Solana, regulated venues |
| Regulatory status | Not authorised under EU MiCA — delisted for EU users on regulated exchanges in 2025; widely used everywhere else | MiCA-authorised in the EU; aligned with the US GENIUS Act framework |
| Cheapest rail | TRON (TRC-20) — cents per transfer | Solana, Polygon, Base — cents per transfer |
| Freeze policy | Freezes addresses at law-enforcement request; publicly lists frozen amounts | Same |
In practice: USDT is the working dollar of the global P2P and remittance economy; USDC is the compliance-friendly dollar of institutions and DeFi. Most people end up holding whichever their counterparties use, and converting between them when needed — USDC (ERC-20) → USDT (TRC-20) is one of the most common swaps on this site.
The network question
The same USDT exists on more than a dozen chains and they are not interchangeable. Sending TRC-20 USDT to an Ethereum address loses it. The four rails that cover almost all real use:
| Rail | Transfer cost | Confirmations on SyntheticSwap | Best for |
|---|---|---|---|
| TRON (TRC-20) | cents | 1 (seconds) | transfers, P2P, exchanges, savings |
| Ethereum (ERC-20) | dollars, varies with gas | 15 (~3 min) | DeFi, institutional flows |
| BNB Chain (BEP-20) | cents | 10 (~30 s) | Binance ecosystem |
| TON | fraction of a Gram | 20 (~2 min) | Telegram wallets |
USDC adds Solana, Polygon and Base (all cents, all fast). The network guide covers each in detail; the ERC-20 → TRC-20 walkthrough shows how to move between rails without an exchange account.
The freeze power
Both issuers can freeze any address on request from law enforcement, and both do — thousands of addresses holding billions of dollars over the years. A frozen balance cannot be moved by anyone but the issuer. This is the defining trade-off of a fiat-backed stablecoin: the peg is credible because the issuer is a regulated, reachable company, and that same reachability means the token is not censorship-resistant.
For an individual the practical rule is: stablecoins are a transit and short-term store, not a censorship-resistant one. If that property matters, hold value in a native asset — Bitcoin, or Monero for privacy — and use stablecoins to move. USDT (TRC-20) → BTC and USDT (TRC-20) → XMR are the standard exits.
The 2025 regulatory settlement
Two frameworks now define the market:
- United States — GENIUS Act (July 2025). Federal licensing for payment stablecoin issuers; full reserve backing in cash and Treasuries; monthly disclosure; issuers must be able to freeze and seize on lawful order. Circle fits the framework directly; Tether has signalled a US-compliant product line while USDT itself remains offshore.
- European Union — MiCA (stablecoin rules since mid-2024). Issuers need EU authorisation and must hold reserves partly in EU banks. USDC is authorised; USDT is not, and regulated EU exchanges removed it for EU customers in early 2025. Individuals can still hold and swap USDT; they just cannot buy it from an EU-licensed exchange.
Neither framework restricts what an individual may hold. Both make the freeze power a legal requirement rather than a policy choice.
Holding stablecoins well
- Pick the rail for the job. TRON for moving dollars cheaply; Ethereum only when a DeFi protocol requires it.
- Self-custody. A stablecoin on an exchange is an IOU on an IOU. In your own wallet it is one issuer's promise, not two.
- Know the exit. Have a swap route to a native asset ready before you need it.
- Do not park large sums for years. Issuer risk is low but not zero; a native asset carries no counterparty.
- Keep an eye on the attestations. Both issuers publish them; the reserve composition is the thing to read.
Frequently asked questions
Can a stablecoin lose its peg? Fiat-backed ones have dipped briefly (USDC to ~$0.88 for a weekend in March 2023 during a bank failure) and recovered. Algorithmic ones have collapsed permanently. Hold only fully reserved, attested tokens.
Is USDT safe to hold in the EU? Legal to hold; not purchasable from EU-licensed exchanges. Account-free swaps work regardless of jurisdiction.
Which is cheaper to move, USDT or USDC? Depends on the rail, not the token. USDT on TRON and USDC on Solana or Base both cost cents.
Can the issuer see who I am? The issuer sees addresses, not names — unless an exchange links them. Self-custody plus account-free swaps keeps it that way.
Where can I convert between stablecoins and networks? The pairs page lists every core route: USDT (ERC-20) → USDT (TRC-20), USDT (BEP-20) → USDT (TRC-20), USDT (TRC-20) → USDT (TON) and more.
USDT (ERC-20) → USDT (TRC-20)
BTC → USDT (TRC-20)
USDC (ERC-20) → USDT (TRC-20)