Does Oxford University require ACT scores for undergraduate admission?

Oxford does not generally require the ACT for undergraduate admission. For most applicants, the key academic requirements are your school qualifications, any Oxford admissions test required for your course, and your interview performance if you are shortlisted. If you are applying from the U.S., Oxford may accept the ACT as part of meeting its academic entry requirements, but it is not a universal requirement for every applicant.

What matters most is whether your course requires an admissions test, whether you meet the academic qualifications listed for U.S. students, and how strong your academic fit is for the subject you are applying to study. Oxford admissions are very course-focused, so they care much more about subject preparation and demonstrated academic strength in that field than about submitting a general test score unless it is part of your qualification route.

So the short answer is no, Oxford does not broadly require ACT scores from all undergraduate applicants. However, if you are applying with U.S. credentials, your ACT may be required or useful as part of meeting the entry requirements for your course, so you should check the exact Oxford course page for the current U.S. qualifications listed there.