What are stablecoins: USDT vs USDC for investors in Brazil

Stablecoins are crypto assets designed to hold a fixed price against a currency, almost always the US dollar. Each USDT or USDC is meant to be worth US$ 1, and the issuer promises to keep one dollar (or an equivalent security) in reserve for every token in circulation. The peg rests on that promise, not on an automatic mechanism. This guide covers how investors in Brazil actually use these assets, how the peg holds, what separates USDT, USDC, BRZ and Drex, which risks are real, and how a sale is taxed.

How investors in Brazil use stablecoins

Three uses account for almost all of the volume.

The first is parking cash between trades. Someone who sells bitcoin and does not want to go back to reais at that moment converts the proceeds into a stablecoin. That avoids two currency conversions and the spread on each one.

The second is dollar exposure. Buying USDC with reais is, for practical purposes, the same as holding dollars in a digital wallet without opening an account abroad. The balance earns nothing on its own. The result in reais depends only on the exchange rate.

The third is a bridge for moving money. A person buys USDT on a Brazilian exchange, sends the token over the blockchain and converts it into local currency on the other side. The costs and the rules of that route are covered in sending money abroad with stablecoins.

The crypto-asset market involves high risk, including significant volatility and the possibility of losing the invested capital. That applies to stablecoins too.

How the peg holds: minting, burning and reserves

The basic mechanism is called mint and burn. An institutional client deposits US$ 1 million with Circle; Circle creates 1 million USDC. When that client redeems, Circle burns the tokens and returns the dollars. The number of tokens in circulation tracks the value of the reserves.

Reserves are the central point. As of September 2026, Circle backs USDC with cash and short-dated US Treasuries, attested monthly by Deloitte. Tether reported about US$ 141 billion in US Treasuries in its first-quarter 2026 report, alongside bitcoin, gold and secured loans, attested quarterly by BDO Italia. An attestation is not a full audit: it is a snapshot of the reserves on one date.

USDT, USDC, BRZ and BRLA, Drex: what changes between them

Circulation figures are from April 2026. Drex is not a private stablecoin but the Central Bank of Brazil's digital currency project: in November 2025 the central bank shut down the platform used in the first two pilot phases, and as of September 2026 there is no public launch date.

The risks that are actually real

Depeg. On March 11, 2023, USDC fell to about US$ 0.88 after Circle disclosed that US$ 3.3 billion of its reserves were stuck at Silicon Valley Bank, which regulators had closed that week. The peg recovered within three days, once the US government guaranteed the deposits. Anyone who sold in the panic locked in a loss of about 12%.

Issuer risk. The token is a promise from the company that issued it. Tether and Circle can freeze addresses at the request of authorities, and both have done so. If the issuer fails, no deposit insurance covers the token holder: not Brazil's FGC, not the FDIC in the United States.

Custody risk. A stablecoin sitting on an exchange adds the exchange's risk to the issuer's risk. In your own wallet, security depends on your keys. That subject is covered in crypto custody: self-custody vs. third-party custody.

Regulatory risk. Since February 2, 2026, Resolution BCB 521/2025 treats the purchase, sale and swap of fiat-referenced virtual assets, plus transfers to self-custody wallets and abroad, as foreign-exchange operations in Brazil. As of September 2026, the decree that would charge 3.5% IOF on stablecoin purchases remains suspended, but the topic may return.

Tax when you sell a stablecoin in Brazil

As of September 2026, selling a stablecoin (or swapping it for another crypto asset) counts as a disposal for Brazil's Receita Federal. The gain is the difference between the sale value in reais and the acquisition cost in reais. If USDC was bought at R$ 5.00 and sold at R$ 5.40, there is an 8% gain, even though the token is still worth US$ 1.

When the sum of all crypto disposals in a month stays at or below R$ 35,000, the gain is exempt. Above that, 15% applies to gains up to R$ 5 million, with progressive rates in higher brackets, and the DARF payment is due on the last business day of the following month. Provisional Measure 1,303/2025, which tried to replace this regime with a flat 17.5% rate and no exemption, lapsed in October 2025.

Since July 2026, DeCripto (Normative Instruction RFB 2,291/2025) has replaced IN 1,888 as the monthly transaction report, and balances still go into the annual return under "Bens e direitos", group 08, code 03. The step by step is in crypto taxes in Brazil explained. Confirm the thresholds with an accountant or with the Vault Tax tool before calculating any tax.

Frequently asked questions

Do stablecoins earn anything?

Not on their own. An idle USDC balance only tracks the dollar against the real. Yield appears when the token is lent out or deposited in a protocol, and at that point the risk becomes the protocol's or the platform's.

USDT or USDC: which one is safer?

USDC has simpler backing (cash and short-dated US Treasuries) and monthly attestations. USDT has more diverse backing and deeper global liquidity. Neither is guaranteed by any government, and many investors split their balance between the two.

Is a stablecoin the same thing as Drex?

No. A stablecoin is issued by a private company and depends on that company's reserves. Drex is a Central Bank of Brazil project, still in pilot, and would be a liability of the central bank itself. As of September 2026, the public cannot buy or use Drex.

Do I need to declare stablecoins on my Brazilian tax return?

Yes. The balance goes under "Bens e direitos" at acquisition cost in reais, and each month's sales must be checked for taxable gains. The calculation can be done with Vault Tax or by an accountant, who validates the result.

Let's talk

Deciding how much of your portfolio to keep in stablecoins, with which issuer and under which custody is an allocation decision, not just a technical one. Vault Capital, a securities advisory firm authorized by Brazil's CVM under CVM Resolution 19/2021, helps investors build that strategy without ever taking custody of their assets. See how our crypto-asset advisory works.