Though we are always looking to expand our services, right now you can only process payments in the country that you activated your Square Account in. If you are visiting another country, you can still use Square to record and track your payments but you won't be able to process any credit cards while outside of the country you activated your Square Account in.
Can I activated an account in Mexico?
Square is not available in Mexico. https://squareup.com/help/us/en/article/4956-international-availability
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