They are different based on my experience in Bangkok. I had withdrawal the same amount on the same date, and there were differences. However, differences were indeed very minor.
It's minor. If you are happy with Schwab, then I really don't think it's worth your time to switch just for the conversion rate. I also use Fidelity as a regular checking account, so it makes more sense for me to just keep most of my spending money all in one account. Also, another minor difference is that fidelity will rebate your ATM right after each transcation, where Schwab will do it once for all at the end of the month.
I have used this card many times on several trips to Thailand. Always continue without conversion. The rate you'd get from Schwab is always excellent and always way better than if you choose conversion from local ATM. However, I have started using Fidelity cash management ATM card now. Same benefits as Schwab with unlimited ATM fee rebate, plus even better conversion rate.
May I ask what if I don't apply for any extension during my stay? For example, can I visit Thailand 4 times in 2026, and each time I only stay 2 weeks and return to my home country?
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