YES they take AMERICAN DOLLARS!!! I was in Mexicali Mexico 9/12/17 - 9/16/17 for my band to sleeve revision with Mexicali Bariatric Center. I tipped my waiter ($5) & my driver($30) because he picked me up, took me to appointments, took me to hotel, then picked me up to take me to hospital & when all was done he drove me back to San Diego for my return trip home. Really that was all that "waited" on me. I'm not a needy type of person so I really didn't have to have anybody do anything for me! This was a VERY POSITIVE EXPERIENCE!! Went by myself & ALL was SAFE & Secure even while caring $7000.00 in cash!!