USDC vs USDT: What They Are and How These Digital Dollars Differ

USDC vs USDT: What They Are and How These Digital Dollars Differ

Andrés Fonseca

Andrés Fonseca

Publish date: 10/23/2026

Last updated: 10/23/2026

USDC and USDT are the two largest digital dollars: digital assets that aim to always be worth 1 U.S. dollar. When comparing USDC vs USDT, the difference lies in who issues them, what they hold in reserve and how often an outside firm reviews it: Circle issues USDC and publishes a reserve report every month, while Tether issues USDT and publishes it every quarter. They also run on different blockchain networks, and that matters every time you send or receive.

The essentials, fast

Who issues them? USDC is issued by Circle Internet Financial, LLC and Circle Internet Financial Europe SAS. USDT is issued by Tether International, S.A. de C.V., a company registered in El Salvador.

What do they hold in reserve? USDC reserves are held in a U.S. government money market fund and in accounts at regulated financial institutions. USDT reserves are mostly in U.S. Treasury bills, and also include gold, bitcoin and secured loans.

What changes for you? The network you send on, the fees of the platform you use and which asset the person paying you, or the person you pay, accepts. Both aim to be worth 1 dollar, but their market price can move.

What USDC is and who issues it

USDC is a digital dollar issued by Circle. According to the August 2026 reserve report, as of August 31 there were more than USD 73 billion of USDC in circulation.

In Europe, Circle Internet Financial Europe SAS holds an electronic money institution license in France, and Circle reported in July 2024 that USDC complies with MiCA, the European Union regulation for crypto-assets. In the United States, Circle reported in August 2026 that it received final approval from the Office of the Comptroller of the Currency (OCC) for a national trust bank.

What USDT is and who issues it

USDT is the digital dollar issued by Tether. It is the largest: as of June 30, 2026, there were more than USD 183 billion in tokens issued, according to its reserve report.

The issuer is Tether International, S.A. de C.V., registered in El Salvador and authorized by that country's National Digital Assets Commission (CNAD) as a stablecoin issuer. Its relevant information document makes clear that this registration does not imply a certification of the token's quality. For the United States, Tether announced a separate asset in January 2026, USA₮, which is issued not by Tether but by Anchorage Digital Bank, N.A.

What backs USDC and USDT?

Both say they hold reserve assets worth the same as or more than the tokens in circulation. What changes is which assets they are and how often they are reviewed:

  USDC (Circle) USDT (Tether)
What the reserve is held in About 85% in the Circle Reserve Fund, a U.S. government money market fund managed by BlackRock; the rest in cash and U.S. Treasury bonds in segregated accounts at regulated financial institutions (August 31, 2026) About 75% in cash and cash equivalents (61% in U.S. Treasury bills); plus 10% in gold, 7% in secured loans, 3% in bitcoin and the rest in other investments (June 30, 2026)
Who reviews it and how often Every month, one of the four largest accounting firms (Big Four), according to Circle Every quarter, BDO Advisory Services, with an assurance report under the ISAE 3000 standard
Surplus over what is issued Reserves equal to or greater than the USDC in circulation Reserves exceed its liabilities by USD 4.11 billion (June 30, 2026)

 

Keep in mind that these reports are point-in-time verifications, not a full audit of the financial statements. The BDO report says so expressly, and Tether states that its audit process with a Big Four firm is still ongoing.

Are USDC and USDT always worth 1 dollar?

They aim to be worth 1 dollar, but there have been times when they were not:

  • USDC, March 2023. Circle had USD 3.3 billion of its reserves, about 8%, at Silicon Valley Bank when that bank failed. USDC traded as low as 87 cents, according to the Federal Reserve, and returned to 1 dollar when the U.S. government guaranteed the deposits.
  • USDT, 2016 to 2019. The CFTC, the U.S. derivatives regulator, concluded in 2021 that during that period Tether did not hold enough reserves to back all of its tokens most of the time, and imposed a fine.

Also, exchanging your tokens directly with the issuer, 1 for 1 dollar, is not available to everyone: Circle and Tether only offer it to certain verified customers. If you are an individual in Colombia, you normally buy, sell or withdraw through a platform, with its own fees.

Why the network you send on matters

USDC and USDT exist on several blockchains, and a transfer only works if the sender and the recipient use the same network. Some examples:

  • USDC: Circle issues it on more than 30 networks, including Ethereum, Solana, Polygon PoS, Base and Arbitrum. In 2024 it stopped issuing it on Tron.
  • USDT: Tether issues it on Tron, Ethereum, Solana, Avalanche and TON, among others, and no longer issues it on networks such as Omni or Algorand.

Before sending, check which asset and which network the destination wallet or platform accepts. On VIIO, for example, the terms and conditions warn that sending to a wrong address or an incompatible network can cause the irrecoverable loss of the assets, because a confirmed transaction cannot be reversed.

In Colombia they are not prohibited, but they are not legal tender. The Banco de la República explains that stablecoins, since they are not issued by central banks, are not recognized as legal tender. According to its December 2025 Financial Stability Report, USDT and USDC represented about 90% of the total stablecoin market capitalization at the end of September 2025.

The Superintendencia Financiera de Colombia warned in 2017 that operations with virtual currencies are not covered by any private or state guarantee, and that it has not authorized the entities it supervises to custody, invest in, intermediate or operate with them.

So, which is better, USDC or USDT?

It depends on what you use it for. These questions help you decide:

  • What does the person paying you, or the person you pay, accept? If a client pays you in USDT over Tron, receiving USDC on another network is of no use to you.
  • What network and fees does your platform have? The cost of sending changes depending on the network and the platform.
  • How much do you care about reserve information? USDC publishes monthly reports and holds most of its reserve in a money market fund. USDT publishes them every quarter and its reserve includes gold, bitcoin and secured loans.

If you want to understand how digital dollars are used to pay in everyday life, read our guide to the digital dollar card.

How they work on VIIO

With VIIO you can receive payments from abroad into your virtual dollar account, by ACH or Wire, or in euros, by SEPA, and send, transfer or spend with your VIIO Visa Card. On VIIO you choose how to hold your funds: USDC or USDT, which track the dollar, or EURC, COPM or PAXG; the assets available at any time are shown in the app. Your balance is not a bank deposit in dollars. If you send to an external wallet, on Polygon sending is free, and on Tron and the other available networks the fee is the higher of USD 5 or 0.3% of the amount; before confirming each transfer you see the applicable fee. More details in which digital assets VIIO uses and in rates and fees.

VIIO is not a financial institution, does not take deposits under Colombian regulations and is not supervised by the Superintendencia Financiera de Colombia. Digital assets available on VIIO are not legal tender or foreign currency and are not covered by FOGAFÍN or any government guarantee. The VIIO Visa Card is operated by Persimon S.A.S.

If you are comparing where to hold your dollars, also check our guide to the dollar account in Colombia.

Frequently asked questions

What is the difference between USDT and USDC? They are issued by different companies (Tether and Circle), have different reserves and are reviewed at different frequencies: USDC every month and USDT every quarter. They also circulate on different networks; for example, Circle no longer issues USDC on Tron, one of the most widely used networks for USDT.

Can you lose money with USDC or USDT? Yes. Their value can move away from 1 dollar, as happened to USDC in March 2023, and if you send to the wrong network or address you can lose the assets. Neither is a bank deposit, and the Superintendencia Financiera warns that operations with virtual currencies are not covered by any private or state guarantee.

Is it legal to hold USDT or USDC in Colombia? They are not prohibited, but they are not legal tender, according to the Banco de la República. Nor are they a bank deposit.

Note from the team: this content is informational and does not constitute financial or legal advice. Reserve and circulation figures change frequently; they are dated and should be checked on each issuer's pages before you decide.

Sources