Recently, many people have been discussing the risks associated with U cards, and this topic certainly deserves attention. To quickly understand the true operational logic of U cards, the key is to clarify the settlement system behind them.

Currently, U card products on the market, regardless of brand, follow a similar transaction settlement path when used domestically — they are all completed through the Visa or Mastercard international clearing networks. This may sound complicated, but using the concept of blockchain as an analogy makes it much simpler.

If you are familiar with interacting with various smart contracts on the blockchain, understanding U cards becomes easy. Essentially, using a U card for transactions is equivalent to interacting with the "protocols" of Visa and Mastercard. Every transaction must go through their clearing systems for verification and settlement.

This also explains why there has been recent sudden attention to the risks of U cards — because once you understand how U cards operate, you can more clearly see potential issues. For example, transaction review mechanisms, the possibility of fund freezes, and cross-border compliance are all controlled by these two major international payment giants.

Therefore, rather than using them blindly, it’s better to first understand exactly how U cards work.