Do I need TOEFL if I studied undergraduate school in a forner country?

I am US citizen; I studied high school in an American boarding school and studied undergraduate school in a Spanish speaking university. Most likely I will do my masters outside the US but there are a couple universities I am looking here.

Do I need to do the TOEFL exam even do I studied high school in an American school???

I believe US citizens don’t take TOEFL. My kids have grown up in India, attended international schools in India. They do not need to take TOEFL because they are Americans.

Each school may have different requirements. Here is what UCLA states:

UCLA Undergraduate Admission

Applicants whose first language, or language of instruction for at least the last three years, is not English, are required to take the Test of English as a Foreign Language (TOEFL) or the International English Language Testing Service (IELTS).

In other words, if your primary language of instruction was NOT English, you probably need to take it.

Thanks for your reply.
Yeap, my problem is that I studied the last four years in Spanish. From what I have been reading, most universities require, at least, that the two last years of study be done in English.