The same asset trades at different prices by exchange. Why the gap does not close.
Crypto prices are set by supply and demand at each exchange. Exchanges in different countries are effectively separate markets, and when buyers crowd into one, only that market's price rises. Normally buying where it is cheap and selling where it is dear would narrow the gap, but where that movement is not free, the gap remains.
The coins themselves move across borders quickly, but the money paying for them does not. Moving currency involves procedures and limits, and bank and exchange checks take time. If the price moves during that window, the expected difference disappears. A gap existing and a gap being capturable are different things.
A widening gap is read as local buying pressure running ahead of overseas. It is therefore often used as a reference for how heated a market has become. A local price below the global one is sometimes read as local participants having stepped back first. These remain interpretations and do not indicate future direction.
Calculating the gap needs a local price, an overseas price and an exchange rate. All three move, so the figure for the same moment differs depending on which rate is used. Numbers that disagree between sources usually differ in their basis.
Trading on the gap ties directly into cross-border transfer rules, currency regulations and taxation. Rules differ by country and change over time. This piece explains why the gap appears and persists, and stops short of how to act on it. Anyone considering it should check the applicable rules first.
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