A lot of countries don't have the high dependence on credit scores as in the US AFAIK, indeed, in quite a few (most, if not all?) European countries "credit cards" are rather uncommon.
Small sample of my own immigrant wife and some immigrant friends. Establishing credit in the US is ridiculously easy. Immigrants with jobs are targeted with credit offers (presumably based on data showing they pay their debts at least as reliably as native-born citizens.) Less than a year after arriving in America my wife had credit cards and a good FICO score, good enough to buy a car at a competitive rate. I didn’t have to co-sign.
Personally I think getting credit for the sake of it is rather silly though. It offends all sorts of sensibilities I have about credit and financial responsibility.
That’s a personal decision. I was addressing the claim that getting credit, or not having credit history, is a challenge for immigrants to the US. It’s a challenge for young American citizens too. I’m sure it’s a challenge but I think it’s a small one. The biggest challenge for immigrants I’ve seen first-hand is getting fluent in English.
