Buying stablecoins: USDC and USDT.

The most widely used stablecoins, such as USDC (Circle) and USDT (Tether), are 'fiat-backed': the issuer holds reserves — typically short-term government debt and cash — worth the value of outstanding coins, and promises to redeem each coin for 1 dollar.

That is a promise, not a legal guarantee like a deposit insurance scheme. The price stays stable as long as the market trusts that promise and the quality and accessibility of the reserves.

USDC is issued by Circle, a US company that periodically publishes external attestations of its reserve composition. USDT is issued by Tether, which was historically less transparent about the exact composition of its reserves, though reporting has expanded in recent years.

Under MiCA, issuers of 'e-money tokens' offered in the EU must meet stricter requirements on reserves and licensing. This has led to some stablecoins (including certain USDT variants) being removed, temporarily or structurally, from EU platforms, while others, like USDC, do have a MiCA-compliant structure.

Stablecoins are bought the same way as other coins, through a MiCA-licensed provider with KYC verification. They're also widely used as an intermediate step when swapping between two other coins, since the value doesn't fluctuate during that swap.

Custody works like ether: stablecoins exist as tokens on multiple networks (Ethereum, Solana and others), so always check which network you're sending on and receiving on. Self-custody removes the risk that a platform holding the coins runs into trouble, but does not remove the issuer risk of the stablecoin itself.

For tax purposes, stablecoins are treated the same as other crypto-assets in Belgium and the Netherlands: no separate regime just because the price is 'stable'. In the Netherlands they count toward box 3 at the value on 1 January — usually close to face value, but not guaranteed to be identical. In Belgium, the normal management versus miscellaneous income question still applies, though price gains on a stablecoin are typically minimal.

The main risk with a stablecoin isn't market volatility but issuer risk: if reserves turn out to be insufficient or inaccessible, the dollar peg can break, temporarily or permanently, as has happened with several smaller stablecoins in the past.